You find yourself in a room with dark gray walls. Medeleev’s image says, “This element is essential for plant life to thrive and is found in heavy clay minerals and the ash from your campfire.” What element are these walls made from?

Answers

Answer 1

Answer:

juvn hgf   jb ujvi i  junk food sux

Explanation:


Related Questions

Police investigating the scene of a sexual assault recover a large blanket that they believe may contain useful physical evidence. They take it to the laboratory of forensic serologist Scott Alden, asking him to test it for the presence of semen. Noticing faint pink stains on the blanket, Scott asks the investigating detective if he is aware of anything that might recently have been spilled on the blanket. The detective reports that an overturned bowl of grapes and watermelon was found at the scene, as well as a broken glass that had contained wine. After the detective departs, Scott chooses and administers what he considers the best test for analysing the piece of evidence in his possession. Three minutes after completion of the test, the blanket shows a positive reaction. What test did Scott choose, and what was his conclusion? Explain your answer.

Answers

Answer:

Acid Phosphatase (AP) Test

Explanation:

Acid phosphate is an enzyme that is found in the body. It is secreted majorly by the prostrate gland into the seminal fluid. The acid phosphatase test is used to test for the presence of semen in items.

Scott chose the acid phosphatase test because it is very useful in testing for semen on large items such as blankets. The reaction time for an acid phosphatase test for semen is less than 30 seconds. Seeing that the test was completed in three minutes, Scott concluded that the positive reaction was as a result of some other fluid.

The detectives reported that an overturned bowl of grapes and watermelon was found at the scene as well as a broken glass that had contained wine. Scott knew that some fruit juices like that of watermelon give a positive reaction to the acid phosphatase test but with  more time that of the semen fluid because the reaction is a very slow one.

Scott concluded that there was no presence of semen on the blanket and therefore there was no sexual assault.

Examine the diagram of the cell cycle.
Which label identifies the stage in which the DNA is copied and the cell grows?

A-W
B-X
C-Y
D-Z

Answers

Explanation:

i think w is the required answer

Which types of energy transformations does a television make?

Electrical energy to energy of motion and heat energy
Electrical energy to heat energy and light energy
Electrical energy to sound energy and energy of motion
Electrical energy to sound energy and light energy

Answers

Answer:

d.

Explanation:

the electricity is why we can hear sounds from the television and see it

If 1 teaspoons of vinegar are equivalent in 60 drops. How many drops of vinegar are there in
1 ½ teaspoons?

Answers

Answer:

90 drops

Explanation:

1 teaspoon = 60 drops

Half a teaspoon = 60 ÷ 2 = 30 drops

1 and a half = 60 + 30 = 90

It’s 90 because if you half 60 it will become 30 60+30=90

A solid sample of Zinc Hydroxide is added to 0.350 L of 0.500 M aqueous Hydrogen Bromide. The solution that remains is still acidic. It is then titrated with 0.500 M NaOH solution, and it takes 88.5 mL of the NaOH solution to reach the equivalence point. What mass of Zinc Hydroxide was added to the Hydrogen Bromide solution?

Answers

Answer:

6.499 g

Explanation:

One part of the aqueous HBr reacted with Zinc Hydroxide following the reaction:

Zn(OH)₂ + 2HBr → ZnBr₂ + 2H₂O

And the remaining HBr reacted with NaOH:

NaOH + HBr → NaBr + H₂O

First we calculate how many HBr moles remained after reacting with Zn(OH)₂. That number equals the number of NaOH moles used in the titration:

0.500 M * 88.5 mL = 44.25 mmol NaOH = mmol HBr

Now we calculate how many moles of HBr reacted with Zn(OH)₂:

Originally there were (350 mL * 0.500 M) 175 mmol HBr175 mmol - 44.25 mmol = 130.75 mmol HBr

Then we convert those 130.75 mmoles of HBr to the Zn(OH)₂ moles they reacted with:

130.75 mmol HBr * [tex]\frac{1mmolZn(OH)_{2}}{2mmolHBr}[/tex] = 65.375 mmol Zn(OH)₂.

Finally we convert Zn(OH)₂ moles to grams:

65.375 mmol Zn(OH)₂ * 99.424 mg/mmol = 6499.8 mg Zn(OH)₂6499.8 mg Zn(OH)₂ / 1000 = 6.499 g

Why is one side of the moon called "the dark side of the moon"?

Answers

Answer:

Option C

Explanation:

The answer is option C or "The amount of time it takes to rotate around it's axis is the same amount of time it takes to revolve around Earth."Remember that the Earth and the Moons amount of time to make a full rotation is almost in sync and they're two sides of the moon, one side we do not see and that's because that side is currently faced away from the Earth which is called the dark side of the moon. Each side has two weeks oh night, and two weeks of day because of how long it takes the moon to revolve, so while we have a side towards the Earth which is illuminated by the sun we have another pointing away in the dark.

Hope this helps.

Lithium diorganocopper (Gilman) reagents are prepared by treatment of an organolithium compound with copper(I) iodide. Decide what lithium diorganocopper (Gilman) reagent is needed to convert 1-bromopropane into propylcyclohexane. Draw the structure of the organolithium compound that is used to prepare Gilman.

Answers

Answer:

See explanation and image attached

Explanation:

The  Gilman reagent is a lithium and copper (diorganocopper) reagent with a general formula R2CuLi.  R is an alkyl or aryl group.

They are useful in the synthesis of alkanes because they react with organic halides to replace the halide group with an R group.

In this particular instance, we intend to synthesize propylcyclohexane. The structure of the  lithium diorganocopper (Gilman) reagent required is shown in the image attached to this answer.

Choose the correct statement regarding the behavior of water.Group of answer choicesThe heat capacity of liquid water is greater than the heat capacity of solid ice.The water phase with the smallest temperature increase when adding 10 kcal of heat is solid ice.Ice has a higher density than liquid water and therefore sinks.The water phase with the smallest temperature increase when adding 10 kcal of heat is gas vapor.The heat capacity of gas vapor is greater than the heat capacity of liquid water.

Answers

Answer:

The water phase with the smallest temperature increase when adding 10 kcal of heat is solid ice.

Explanation:

The rest of the statements are incorrect. The density of ice is lower than the density of water. The heat capacity of solid ice is greater almost twice the heat capacity of the liquid water. The heat capacity of vapors is less than heat capacity of liquid.

Which orbital is partially filled in the Zirconium (ZI) atom?

Answers

Answer:

4d orbital.

Explanation:

Hello!

In this case, since zirconium's atomic number is 40, we fill in the electron configuration up to 40 as shown below:

[tex]1s^2,2s^2,2p^6, 3s^2,3p^6,4s^2,3d^{10},4p^6,5s^2,4d^2[/tex]

Thus, the orbital 4d is partially filled.

Best regards!

ou are a work study for the chemistry department. Your supervisor has just asked you to prepare 500 mL of 3 M HCl for tomorrow’s undergraduate experiment. In the stockroom explorer, you will find a cabinet called "stock solutions". Open this cabinet to find a 2.5 L bottled labeled "11.6 M HCl". The concentration of the HCl is 11.6 M. Please prepare a flask

Answers

Answer:

Add to a 500mL volumetric flask 300mL of water, the 129mL of the 11.6M HCl solution and then complete to volume with water

Explanation:

To make 500mL = 0.500L of a 3M HCl from the 11.6M HCl stock we need first to find the moles of HCl we need:

Moles HCl:

0.500L * (3mol / L) = 1.5 moles of HCl are needed

These moles are obtained from the 11.6M HCl solution. The volume required is:

1.5mol * (1L / 11.6moles HCl) = 0.129L = 129mL must be added to the solution.

That means to prepare the 500mL of the 3M HCl you need to:

Add to a 500mL volumetric flask 300mL of water, the 129mL of the 11.6M HCl solution and then complete to volume with water

Answer:

Calculation: 11.6 M × V = 3.0 M × 0.500 liters

V = 0.13 liters

Steps for dilution:

Measure out 0.13 liters of the concentrated solution of 11.6 M HCl using a volumetric pipet.

Transfer this into solution into a 500 milliliter volumetric flask.

Add water to the flask until it reaches a total volume of 500 milliliters.

Solution: V = 0.13 liters

Explanation:

compute the mass-specific enthalpy change associated with Nz that is undergoing a change in state from 400 k to 800 k

Answers

Answer:

The correct answer is "430 kJ/kg". A further explanation is given below.

Explanation:

The given values are:

T₁ = 400 k

T₂ = 800 k

The average temperature will be:

= [tex]\frac{T_1+T_2}{2}[/tex]

= [tex]\frac{400+800}{2}[/tex]

= [tex]600 \ k[/tex]

From table,

At 600 k the [tex]C p[/tex] will be = 1.075

Now,

⇒ The specific enthalpy = [tex]Cp(T_2-T_1)[/tex]

⇒                                [tex]\Delta h=1.075 (800-700)[/tex]

⇒                                      [tex]=430 \ kJ/kg[/tex]

Give the formula of the alkanes his molecule contains 28 hydrogen atoms

Answers

Answer:

jayfeather friend me

Explanation:

Table 1. Summary of the Straight-Chain Alkanes

Name Formula Number of Structural Isomers

Octadecane C18H38

Nonadecane C19H40

Eicosane C20H42 366,319 (!)

29 more rows

The formula of the alkanes the molecule contains 28 hydrogen atoms is [tex]C_1_3H_2_8[/tex], i.e., tridecane.

What are alkanes?

Alkanes are organic compounds made up entirely of single-bonded carbon and hydrogen atoms with no other functional groups.

Alkanes have the general formula CnH2n+2 and are classified into three types: linear straight-chain alkanes, branched alkanes, and cycloalkanes.

Alkanes are important raw materials in the chemical industry and the main component of gasoline and lubricants.

Natural gas is primarily composed of methane and ethane and is used for heating, cooking, and power generation (gas turbines).

Natural gas and petroleum are separated from the alkanes. Natural gas is primarily composed of methane, with trace amounts of other low molecular weight alkanes.

All other alkanes are derived from petroleum, which is a complex mixture of many compounds.

Here, the formula for 28 hydrogen atom containing alkane is

[tex]C_1_3H_2_8[/tex]

Thus, this given formula is of tridecane.

For more details regarding alkanes, visit:

https://brainly.com/question/4260635

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a reaction vessel contains a small piece of magnesium metal and air (20%) of which is oxygen gas. The mixture is ignited and burns with a burst of light and heat, producing solid magneisum oxide. The mass of mgO, however, is less than the initital mass of magnesium and oxygen combined. What loss of mass

Answers

Answer: see below

Explanation:

Mg burning in air gives MgO and a smaller amount of Mg3N2

2Mg+O2=2MgO. 2*24.3+32=2*40.3

3Mg+N2=Mg3N2

Ignoring the nitride, MgO loss of mass during the reaction can be ascribed to

(1) relativistic loss as energy (too small to be measurable)

(2) During the reaction, which is strongly exothermic, a fraction f the material is blown off as tiny particles which adhere to the vessel.

If you were to burn a candle inside of a closed jar and the mass of the
closed jar and candle was 50 grams to begin with, what would the mass of
the jar and smoke be after the candle is done burning?

Answers

Answer:

50g

Explanation:

At the end of the burning process, the mass of the jar and smoke should be 50g after the candle burning is done.

In most systems, the law of conservation of matter finds expression. According to this law "matter is neither created nor destroyed but atoms are rearranged".

In this kind of system, no matter is allowed to escaped and the starting mass of the reactants compared to that of the product will be the same.

Pls answer this ASAP thank you

Answers

Answer:

The anwer is not D the anwer is A

Explanation:

Help pls!!!!!!!!!!!!!!!!!!!

Answers

Answer:

water

Explanation:

water is made up of both hydrogen and oxygen (h2o)

How many molecules are in 97.21 grams of Sodium Chloride (NaCl)?

Answers

1.66 is the answer because it’s is

Don’t skip please!!! I need help

Answers

Further explanation

Given

Atomic symbol

Required

Atomic composition

Solution

Atomic number = number of protons = number of electrons

Mass Number (A) is the sum of protons and neutrons

Number of protons and Number of Neutrons  in nucleus

Number of electrons in the shell

From the picture:

protons = 3

neutrons = 4

electrons = 3

atomic number = protons = electrons = 3

mass number = protons + neutrons = 3+4 = 7

How does the appearance of a substance change when it
changes phase?

Answers

Answer:

Melting: the substance changes back from the solid to the liquid. Condensation: the substance changes from a gas to a liquid. Vaporization: the substance changes from a liquid to a gas. Sublimation: the substance changes directly from a solid to a gas without going through the liquid phase.

Explanation:

The change in appearance of a substance when it changes its phase includes :

Change in volume Change in texture and Change in shape

Change in volume : when a liquid substance is heated to its boiling point ( vaporization) the volume of the liquid substance will change when it turns into gas because gases have no definite volume or shape.

Change in Texture: When water freezes it changes its state from a liquid state to a solid state, also the appearance of the liquid water will undergo changes in its texture when it is in its' solid state ( i.e. the texture of ice is not exactly the texture of liquid water )  

Change in shape : when a solid substance changes its state from solid to gas ( sublimation ) the shape of the solid substance will be lost during the phase change.

Hence we can conclude that the change in the appearance of a substance when it changes its phase include. Change in volume, Change in texture and Change in shape.    

Learn more : https://brainly.com/question/16785581

Would you consider an aquifer a renewable resource? Why or why not?

Answers

Answer:

an aquifer is a renewable resource

Explanation:

Aquifers are defined as the groundwater found deep in the layers of rocks.

An aquifer is considered as a renewable resource because groundwater is renewed over time. Aquifers are water resources and follow hydrological cycle through which it can renew itself.

Some of the deep aquifers are considered as  nonrenewable resource because it toll hundreds of years to accumulate.

Hence, the correct answer is yes an aquifer is a renewable resource except some deep aquifers.

Consider a reaction that connects the ends of a chain of carbons to form a ring. The closure of the ring results in the formation of a new chemical bond, with the bonding electrons going into a bonding sigma molecular orbital at a lower energy. Which of the following statements correctly describes the resulting enthalpy, entropy, and heat changes? Mark all that are correct.
A. The entropy of the surroundings decreases (AS surr < 0) because the closure of the ring results in fewer conformations for the system.
B. The system releases energy to the environment, because its internal energy decreases.
C. The entropy of the surroundings increases (AS surr > 0) because the surroundings absorb heat released by the reaction, and become more disordered.
D. The entropy of the system decreases (AS sys < 0) because the closure of the ring reduces the number of conformations the ring can adopt.
E. The enthalpy or internal energy of the system decreases (AH sys < 0) because the electrons that form the bond enter an orbital that is at a lower energy.

Answers

Answer:

The system releases energy to the environment, because its internal energy decreases.

The entropy of the surroundings increases (AS surr > 0) because the surroundings absorb heat released by the reaction, and become more disordered.

The entropy of the system decreases (AS sys < 0) because the closure of the ring reduces the number of conformations the ring can adopt.

The enthalpy or internal energy of the system decreases (AH sys < 0) because the electrons that form the bond enter an orbital that is at a lower energy.

Explanation:

Now we know that when a reaction is exothermic heat is given off. In this case, we have a reaction that connects the ends of a chain of carbons to form a ring.  The bonding electrons now move into a lower energy bonding sigma molecular orbital.

This leads to a decrease in the entropy and enthalpy of the system because energy is given off, the closure of the ring reduces the number of conformations the ring can adopt and  the electrons that form the bond enter an orbital that is at a lower energy.

The entropy of the surroundings is increased as energy is given out. The surroundings absorb heat released by the reaction, and become more disordered.

The picture has my question

Answers

Answer:

b or c

Explanation:

The answer is C.

Explanation: Between the chemicals equation it forwards out to the certain equation which also equals too the equation

Calculate the number of moles in 15.5g of CaSO4.5H2O

Answers

Answer:

No. of moles = 0.0685

Explanation:

Given mass, m = 15.5g

We need to find the number of moles in 15.5 g of CaSO₄.5H2O

First, we find the mass of CaSO₄.5H2O.

M = (1×40)+(1×32)+(4×16)+(5×18)

M = 226 g/mol

We know that,

Number of moles = given mass/molar mass

[tex]n=\dfrac{15.5\ g}{226\ g/mol}\\\\n=0.0685\ \text{mol}[/tex]

Hence, there are 0.0685 moles in 15.5 g of CaSO₄.5H2O.

How many atoms are in 0.580 moles of CO2?

Answers

Answer:

[tex]1.05x10^{24}atoms[/tex]

Explanation:

Hello!

In this case, according to the definition of the Avogadro's number, it is possible to realize that one molecule of CO2 contains 3 moles of atoms, one of carbon and two of oxygen, thus, we have:

[tex]0.580molCO_2*\frac{3mol\ atoms}{1molCO_2} =1.74mol\ atoms[/tex]

Then, we use the Avogadro's number to obtain:

[tex]1.74mol\ atoms*\frac{6.022x10^{23}atoms}{1mol\ atoms} \\\\1.05x10^{24}atoms[/tex]

Best regards!

Sound waves are longitudinal, mechanical, compression waves.
A. True
B. False

Answers

Answer:

True

Explanation:

Sound waves traveling through air are indeed longitudinal waves with compressions and rarefactions. As sound passes through air (or any fluid medium), the particles of air do not vibrate in a transverse manner.

Answer:

true

Explanation:

ape x

What is the answer for number 9 in the Half-life gizmo activity B.

Answers

What ? I Dnt understand ?

Density of water calculation using a 10 mL graduated cylinder

10 mL graduated cylinder + 10 mL unknown liquid (g) 10 mL graduated cylinder (g) Volume of liquid (mL) Density (g/mL)
Trial 1 19.731 9.861 10.0
Trial 2 19.831 9.861 10.0
Trial 3 19.831 9.861 10.0
Trial 4 19.771 9.861 10.0
Trial 5 19.751 9.861 10.0

Required:
Calculate the average density for the gradudated cylinder measurements.

Answers

Answer:

Average density of the liquid = 0.992 g/mL

Explanation:

Density = mass/volume

mass of liquid = (mass of liquid + mass of cylinder) - mass of cylinder

Trial 1: mass of liquid = 19.731 - 9.861 = 9.87

volume of liquid = 10 mL

density of liquid = 9.87 g / 10 mL = 0.987 g/mL

Trial 2: mass of liquid = 19.831 - 9.861 = 9.97

volume of liquid = 10 mL

density of liquid = 9.97 g / 10 mL = 0.997 g/mL

Trial 3: mass of liquid = 19.831 - 9.861 = 9.97

volume of liquid = 10 mL

density of liquid = 9.97 g / 10 mL = 0.997 g/mL

Trial 4: mass of liquid = 19.771 - 9.861 = 9.91

volume of liquid = 10 mL

density of liquid = 9.91 g / 10 mL = 0.991 g/mL

Trial 5: mass of liquid = 19.751 - 9.861 = 9.89

volume of liquid = 10 mL

density of liquid = 9.89 g / 10 mL = 0.989 g/mL

Average density = (0.987 + 0.997 + 0.997 + 0.991 + 0.989)/5 = 4.961/5

Average density of the liquid = 0.992 g/mL

There is a third bromobutene structure that could have been formed in the addition of HBr to butadiene: cis-1-bromor-2-butene (the cis isomer of structure 2). Draw this structure. Would you predict (no calculation) its heat of formation to be more or less negative that the trans isomer? Explain.

Answers

Answer:

its less negative hope I helped buster

Because trans isomers are more stable than cis isomers, the cis isomer will have a less negative heat of formation than the trans isomer.

What are cis- and trans- isomers?

Cis- and trans isomers are compounds that have different configurations in space because of the presence of a rigid structure or functional groups in their molecule.

Cis atoms have functional groups on the same side.

Trans isomers have functional groups on alternate different.

The structure of cis-1-bromor-2-butene is attached.

Generally, trans isomers are more stable than cis isomers..

Stable compounds have more negative heat of formation while unstable compounds have less negative heat of formation.

Therefore, the cis isomer will have a less negative heat of formation than the trans isomer.

Learn more about cis and trans isomers at: https://brainly.com/question/4625349

Which of these describes the essential conclusion of the Rutherford experiment? The atom contains a very small nucleus that contains most of its mass. The proton is positively charged and the neutron has no charge? Atoms are solid spheres with electrons suspended in them like chocolate chips in a cookie. Mass is neither made nor consumed in a chemical reaction.

Answers

Answer:

The atom contains a vey small small nucleus that contains most of its mass.

Explanation:

The Rutherford gold leaf experiment concluded that most (99%) of all the mass of an atom is in the nucleus of the atom, that the nucleus is very small (105 times small than the size of the atom) and that is is positively charged.

Calculate the pH of a solution that is prepared by dissolving 0.23 mol of hydrofluoric acid (HF) and 0.57 mol of hypochlorous acid (HClO) in water and diluting to 3.60 L. Also, calculate the equilibrium concentrations of HF, F2, HClO, and ClO2. (Hint: The pH will be determined by the stronger acid of this pair.)

Answers

Answer:

The equilibrium concentrations of HF = 0.058 , F2 = 0.006M , HClO =0.16M , and ClO2 = 7.7 × 10⁻⁷M.

Explanation:

The Ka values for HClO₃ and HF are given as 2.9 × 10⁻⁸ and 6.6 × 10⁻⁴ respectively. The molar concentration for HF = 0.23/ 3.60L = 0.064 M and 0.57/ 3.60 = 0.16 M.

When HF is reacted with water, it ionizes to form H₃O⁺ and F⁻. The concentration of H₃O⁺ and F⁻ can be calculated below:

HF(aq) <------------------------> H30^+ + F^-.

Ka = [H^+] [F^-]/[HF] .

6.6× 10^-4 = [x][x]/ ( 0.064- x).

x = 0.0060 M.

The concentration of H₃O⁺ and F⁻ = 0.0060 M respectively.

The pH = - log [ H₃O⁺ ] = -log [0.0060] = 2.22.

When HClO is reacted with water, it ionizes to form H₃O⁺ and F⁻. The concentration of H₃O⁺ and ClO⁻ can be calculated below:

HClO(aq) <------------------------> H30^+ + ClO^-.

Ka = [H^+] [ClO^-]/[HClO] .

6.6× 10^-4 = [0.006 + x] [x]/ ( 0.16 - x).

x = 7.7 × 10^-7M.

[ClO^-] = 7.7 × 10^-7 M.

[HClO] = 0.16 - 7.7 × 10^-7 = 0.16M.

[F^-] = 0.006 M.

[HF] = 0.064 - 0.006 = 0.058 M.

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