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

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.

Answer:

44.84 ml

Explanation:

14.86

+

15.0

+

14.980

_______

44.84

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!

Answer:

water

Explanation:

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

Answer:

Measure the volume of water poured into a graduated cylinder, then place the object in the water and remeasure the volume. The difference between the two volume measurements is the volume of the object. Now simply divide the mass by the volume to calculate the density of the object.

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.

The food has 23629.64 cal

Given

mass = 1000 g of water

temperature increases 23.65 * C

Required

The energy of the food

Solution

Heat absorbed by water :

Q = m . c . Δt

Q = 1000 g x 4.184 J/g°C x 23.65 °C

Q = 98951.6 J

1 Joules = 0.2388 Calories

98951.6 J = 23629.64 cal

Answer:

i wish i know

Explanation:

i wish i know

The specific heat : c = 0.306 J/g K

Given

Heat = 35.2 J

Mass = 16 g

Temperature difference : 7.2 K =

Required

The specific heat

Solution

Heat can be calculated using the formula:  

Q = mc∆T  

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

Input the value :

c = Q / m.∆T  

c = 35.2 / 16 x 7.2

c = 0.306 J/g K

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.

Answer: C ) The reactants are higher in energy than the products

Explanation:

The enthalpy that is a state variable that identifies the content of heat. Then the change of enthalpy for the exothermic reactions is negative, meaning that the energy of the products is lower than the energy of the reactants.

Answer:

Boiling Water

Explanation:

Boiling water is an example of physical change and not and not a chemical change because the water vapor still has the same molecular structure as liquid water.If the bubbles were caused by the decomposition of a molecule into gas then boiling would be a chemical change.

Answer:

A chemical change results from a chemical reaction, while a physical change is when matter changes forms but not chemical identity. Examples of chemical changes are burning, cooking, rusting, and rotting. Examples of physical changes are boiling, melting, freezing, and shredding

Explanation:

sorry i can only figure out 1 but the answer is

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124

hope you do good on your test :D

Answer:

Covalent-network (also called atomic) solids—Made up of atoms connected by covalent bonds; the intermolecular forces are covalent bonds as well. Characterized as being very hard with very high melting points and being poor conductors. Examples of this type of solid are diamond and graphite, and the fullerenes.

I hope it's helpful!

Answer:

network solid

Explanation:

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!

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

Answer:

1. aa

2. They have similar DNA

Explanation:

1. According to the question 1, wrinkled seeds (A) are dominant over round seeds (a) in pea plants. This means that, based on the law of dominance proposed by Mendel, wrinkled seeds will be expressed over round seeds in a heterozygous state (Aa).

However, since the round seed phenotype is a recessive trait, it will only be expressed when the alleles for round seeds (a) are the same in the gene i.e. aa genotype.

2. Based on the information in question 2, Ricky, who is working on a family tree for his school project, realizes that his close relatives all look similar in the pictures he collected. This is possible because of the SIMILARITY OF THEIR DNA (genetic material). Note that, relatives are connected by the genes that are inherited from one another, hence, they possess a similar DNA, which is the most valid reason for the resemblance.

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:

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.

Answer:

369 ml

Explanation:

Mass of Aluminium (Al) = 20 g

Molar concentration =  2.007M

Molar concentration = Number of moles / Volume

The relationship between mass and number of moles;

Number of moles = Mass / Molar mass

Number of moles = 20 / 27 = 0.741 mol

2.007  = 0.741  / Volume

Volume = 0.741 / 2.007 = 0.369 L

converting to millilitres by multiplying by 1000

Volume = 0.369 * 1000 = 369 ml

Answer:

Density, d = 5.96 g/mL

Explanation:

Given that,

Mass, m = 105 g

Volume, V = 17.6 mL

We need to find the density of the substance. So,

[tex]d=\dfrac{m}{V}\\\\d=\dfrac{105\ g}{17.6\ mL}\\\\d=5.96\ g/mL[/tex]

So, the density of the substance is 5.96 g/mL.

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.

Answer:

b or c

Explanation:

Answer:

What is ^ for?

Explanation:

Answer:

55.6 °C

Explanation:

From the question given above, the following data were obtained:

Mass (M) of diamond = 32.0 g

Initial temperature (T₁) = 33.5°C

Heat (Q) required = 360 J

Specific heat capacity (C) of diamond = 0.509 J/gºC

Final temperature (T₂) =?

Next, we shall determine the change in temperature. This can be obtained as follow:

The final temperature can be obtained as follow:

Mass (M) of diamond = 32.0 g

Heat (Q) required = 360 J

Specific heat capacity (C) of diamond = 0.509 J/gºC

Change in temperature (ΔT ) =?

Q = MCΔT

360 = 32 × 0.509 × ΔT

360 = 16.288 × ΔT

Divide both side by 16.288

ΔT = 360 / 16.288

ΔT = 22.1 °C

Finally, we shall determine the final temperature. This can be obtained as follow:

Initial temperature (T₁) = 33.5°C

Change in temperature (ΔT ) = 22.1 °C

Final temperature (T₂) =?

ΔT = T₂ – T₁

22.1 = T₂ – 33.5

Collect like terms

22.1 + 33.5 = T₂

T₂ = 55.6 °C

Therefore, the final temperature is 55.6 °C.

Answer: 1075.5 mph

Explanation:anything moving at 4.78*10^4 cm/sec

equivalent to

cm —> miles = 1/1.6*10^5

sec —> hr = 1/3600

[4.78*10^4]*3600/1.6*10^5 = 1075.5 mph

Answer:

Krypton

Explanation:

Answer:

The anwer is not D the anwer is A

Explanation: