Answer:
Ge
Explanation:
pretty sure im on high school 12th
What is the molarity of a 300.0 mL solution containing 25.0 g of NaCl?
Answer:
1,43 M
Explanation:
molair mass NaCl = 58,44 g/mol
You need to calculate how many moles 25 g is:
25 g / 58,44 g/mol = 0,4278 mol
0,4278 mol / 0,3 L = 1,43 M
30)
Cosmologists believe that the universe is expanding and that it has been expanding since the Big Bang. Astronomers
viewing distant stars see evidence of this expansion in which phenomenon?
A)
Red shift
B)
Blue shift
Gamma pulse
D)
Background radiation
Answer:
i did this so the next person can have brainliest
Explanation:
If the point of the nail can be approximated as a circle with a radius 2.00×10^-3m What is the pressure in MPa exerted on the wall if a hammer strikes the nail with a force of 104 N
Answer:
8.28 MPa
Explanation:
From the question given above, the following data were obtained:
Radius (r) = 2×10¯³ m
Force applied (F) = 104 N
Pressure (P) =?
Next, we shall determine the area of the nail (i.e circle). This can be obtained as follow:
Radius (r) = 2×10¯³ m
Area (A) of circle =?
Pi (π) = 3.14
A = πr²
A = 3.14 × (2×10¯³)²
A = 3.14 × 4×10¯⁶
A = 1.256×10¯⁵ m²
Next, we shall determine the pressure. This can be obtained as follow:
Force applied (F) = 104 N
Area (A) = 1.256×10¯⁵ m²
Pressure (P) =?
P = F / A
P = 104 / 1.256×10¯⁵
P = 8280254.78 Nm¯²
Finally, we shall convert 8280254.78 Nm¯² to MPa. This can be obtained as follow:
1 Nm¯² = 1×10¯⁶ MPa
Therefore,
8280254.78 Nm¯² = 8280254.78 Nm¯² × 1×10¯⁶ MPa / 1 Nm¯²
8280254.78 Nm¯² = 8.28 MPa
Thus, the pressure exerted on the wall is 8.28 MPa
C6H12O6 O3 NF3 Co KNO3 H2 CO
Which one of these are molecules list all that apply
9. This type of bond consists of closely packed cations and loosely held valence e- rather than
neutral atoms.
a. lonic
b. Covalent
c. Metallic
d. polyatomic
what is the answer to this
Answer:
Explanation:
i may be wrong but i think its b
Answer:
B Ndaira is right for real
Question 4 of 20
A student is performing experiments on a particular substance. Which
statement is an observation of a chemical property of the substance?
A. Its viscosity decreases.
B. It boils.
C. Electricity passes through it.
D. It reacts with acid.
SUBMIT
Answer:
D
Explanation:
Reacting with acid is the only chemical property out of the 4 options. The rest are physical
which of the substance changes when it is heated
A . mass
B . volume
C . weight
D . brass
Answer:
mass
Explanation:
Answer:
The answer is C.
Explanation:
If you have absolutely identical objects that have the same weight exactly when they are at the same temperature, then when one object is heated, it will weigh more.
Hope this helps :)
-ilovejiminssi♡
You start with 2.5g of magnesium and add it to 400mL of CO2 at 23 o C and 1atm. How many grams of magnesium oxide will be formed?
Answer:
0.664 g are formed by the reaction.
Explanation:
First of all, we determine the reaction:
Mg + CO₂ → MgO + CO
We need to determine the moles of the CO₂ by the Ideal Gases Law.
We convert to L, the volume → 400 mL = 0.4L
T° → 23°C + 273 = 296K
P . V = n . R .T
n = P . V / R .T
n = (1 atm . 0.4L) / (0.082 . 296K) → 0.0165 moles
Moles of Mg → 2.5 g . 1mol / 24.3g = 0.103 moles
As ratio is 1:1, CO₂ is the limiting reactant.
For 1 mol of Mg, we need 1 mol of gas
Then, for 0.103 moles of Mg, we need 0.103 moles of gas, but we only have 0.0165 moles.
If we see the product side, ratio is also 1:1
0.0165 moles of CO₂ must produce 0.0165 moles of MgO.
We convert the moles to mass → 0.0165 mol . 40.3 g /1mol = 0.664 g
When silver nitrate (AgNO3) dissolves in water, the temperature of the solution decreases.
Explain your answer
Answer:
The enthalpy of solution for AgNO3 is positive because the temperature of the solution decreases (the dissolution is endothermic). Hsol = Hsolute + Hsolvent + HmixHsolute and Hsolvent are endothermic because energy is required to overcome intermolecular forces and separate solute and solvent particles.
Answer:
the enthalpy of solution for agno3 is positive because the temperature of the solution decreases. (the dissolution is endothermic.)
Delta H sol=delta HSolute +delta H solvent +delta H mix
HSolute and H solvent are endothermic because energy is required to overcome intermolecular forces and separate solute and solvent particles.
H mix is exothermic because energy is released when intermolecular forces form between solute and solvent particles.
if the overall enthalpy of solution is positive, then HSolute + H solvent must be larger in magnitude than H mix.
Explanation:
correct on edge2021
I WILL GIVE YOU BRANILY PLS
Answer:
what dose this even mean?
Explanation:
What does the illustration indicate?
Answer: A
Explanation:
20.What do carbon and silicon have in common?
a.They belong to the same column (family), therefore they have the same number of valence electrons.
b.They belong to the same column (family), therefore they have the same number of total electrons.
c.They belong to the same column (family), therefore they have the same number of energy levels.
d.They belong to the same column (family), therefore they have the same number of protons.
The breaking down or wearing away of rock and soil is known as... A. earthquake
B. global shift C. weathering D. deposition
Answer:
the breaking down of rock is known as weathering
According to the enthalpy diagram below, which of the following statements is true?
Arrows A and D represent the enthalpy of the intermediate chemical reactions.
Arrow C represents the enthalpy of the overall chemical reaction.
Arrow C indicates that the third intermediate reaction is exothermic.
Arrow B indicates that the second intermediate reaction is exothermic.
According to the enthalpy diagram true statement is that Arrow C indicates that third intermediate reaction is exothermic in nature.
What is enthalpy of reaction?Enthalpy of the reaction gives idea about the exchange of heat during the whole chemical reaction process.
Arrow A and Arrow B represents that first and second intermediate reaction is endothermic.Arrow C indicates that third intermediate reaction is exothermic in nature.Hence Arrow C indicates that the third intermediate reaction is exothermic is true statement.
To know more about enthalpy, visit the below link:
https://brainly.com/question/14291557
#SPJ2
Answer: c
Explanation:
A chemist analyzes two samples. One sample contains 14g of element x and 6.0 g of element y. The second sample contains 28 g of element x and samples are the same substance
Answer:
Explanation:
Here's the complete question:
A chemist analyzes two samples.One sample contains 14g of element x and 6.0g of element y.The second sample contains 28g of element x and 6.0g of element y. Does it appear that the two samples are the same substance?
The two samples that we are given in the question are different. They are not the same thing because we can deduce that their components ratio are different.
Sample One contains 14g of element x and 6.0g of element y. The ratio of element x to y is 14/6 = 7/3 = 7:3.
Sample Two contains 28g of element x and 6.0g of element y. The ratio of element x to y is 28/6 = 14/3 = 14:3.
Therefore, they have different ratio for their components and are therefore not thesame.
What is on the left side of the arrow 2H2+1O2 --> 2H2O
Answer:
The correct answer is - reactants.
Explanation:
In any chemical reaction, there is an arrow that distinguishes the two major components of the chemical equation by placed in between them. These two components are reactants and products.
OftenlThe reactants placed on the left side of a chemical equation and the products placed on the right side of a chemical equation. In this given case, the reactants 2H2 + 1O2 are placed on the left side of the equation.
Why is red tide dangerous to ocean animals?
Answer:
Karenia brevis produces toxins called brevetoxins that affect a variety of marine wildlife. Aquatic organisms can be exposed to brevetoxins in several ways: coming into contact with K. brevis cells or toxins in the water, ingesting cells, inhaling toxins and consuming toxic prey.
Explanation:
A chemical reaction that is expected to form 325.0 gof product only forms 123.8 g of product. What is the percent yield of this reaction?
38.1%
61.9%
201.2%
262.5%
Answer:
[tex]\boxed {\boxed {\sf A. \ 38.1 \%}}[/tex]
Explanation:
Percent yield is the ratio of the amount actually produced to how much could theoretically be produced. It is found using this formula:
[tex]\% \ yield = \frac{actual \ yield}{theoretical \ yield} *100[/tex]
For this reaction, the theoretical or expected yield is 325.0 grams. The actual yield is 123.8 grams.
[tex]\% \ yield = \frac{ 123.8 \ g }{325.0 \ g }*100[/tex]
Divide.
[tex]\% \ yield = 0.380923077 *100[/tex]
[tex]\% \ yield = 38.0923077[/tex]
Round to the nearest hundredth. The 9 in the hundredth place tells us to round the 0 to a 1 .
[tex]\% \ yield \approx 38.1[/tex]
The percent yield is about 38.1%
Answer:
38.1%
Explanation:
Which statement is best illustrated in the diagram above regarding how the Sun's energy affects the Earth's surface from June through September in the Northern Hemisphere? The season changes from autumn to winter, daylight hours decrease, and infrared radiation is the weakest during the June solstice. B The season changes from winter to spring, daylight hours increase, and infrared radiation is the weakest during the September equinox. C The season changes from summer to autumn, daylight hours decrease, and infrared radiation is the strongest during the June solstice. The season changes from spring to summer, daylight hours increase, and infrared radiation is the strongest during the September equinox.
Answer:
I'm sorry but there is no diagram above.
Which of the following is a limitation of using a model to study a natural event?
A.
The results of a model event are often much more accurate than those of the actual event.
B.
The model and the results it generates will have no relation at all to the actual event.
C.
The size and design of the model will be too similar to the actual event.
D.
The results of a model event may not be similar enough to the results of the actual event.
Answer:
D
Explanation:
why i say that is because take for example a volcano, when you make a model, you'll see what takes place in a real eruption but in real life the lava would burn things in its path, the model volcano may not. That's just an example
Answer:
D
Explanation:
I got it right on study island
i really need help with this
Answer:
the process shown here is endocytosis.
Explanation:
endocytosis is a process of taking something inside the cell..
If 276 g of dinitrogen tetroxide and 64.0 g of hydrazine are mixed, how many grams of nitrogen gas can you produce?
Answer:
84 g of N₂
Explanation:
We begin from the reaction:
N₂O₄ + 2N₂H₄ → 3N₂ + 4H₂O
1st step: Find out the limiting reactant.
We convert the mass to moles.
276 g . 1mol/ 92g = 3 moles of N₂O₄
64 g . 1mol / 32g = 2 moles of hidrazine
Limiting reactant is the hydrazine. Ratio is 1:2, then for 3 moles of tetroixde I may need 6 moles of N₂H₄. (But I only have 2).
To determine the grams of produced nitrogen we see stoichiometry (2:3)
2 moles of hydrazine can produce 3 moles of N₂
Definetaly our 2 moles make 3 moles of gas.
We convert the moles to mass.
3 mol . 28g /1mol = 84 g of N₂
The freezing point of a substance is the
at
which it freezes.
Answer:
reff lagay mo yung ilalagay mo
Answer:
Freezing point is the temperature at which a liquid becomes a solid at normal atmospheric pressure. Alternatively, a melting point is the temperature at which a solid becomes a liquid at normal atmospheric pressure.
How do parasites affect their hosts?
They help their hosts by consuming or using their cells.
They help their hosts by growing in size.
O They harm their hosts by growing in size.
They harm their hosts by using their hosts as a food source.
Convert 6.24 x 10g to standard notation.
Answer:
3.45 x 10^5
Explanation:
A sample of Oxygen gas is in a cylinder at constant temperature. What would happen to the pressure of the gas if the volume was
smooshed down to half its original size? Decreasing the volume by a factor of 2.
Answer:
This means that the pressure would become double of it's initial pressure.
Explanation:
Key statements:
- Constant temperature
- What happens to the pressure of the gas if the volume was
smooshed down to half its original size?
Basically the question is asking about the relationship between pressure and volume at constant temperature. This is given by Boyle's law.
Boyle's law states that the volume of a fixed mass of gas is inversely proportional to it's volume at a fixed temperature.
This is given by;
P1V1 = P2V2
Where;
P1 = Initial pressure
P2 = Final pressure
V1 = Initial Volume
V2 = Final Volume
From the question;
V2 = V1/2
Inserting it into the equation;
P1 V1 = P2 V1/2
Divide all through by V1
P1 = P2 /2
P2 = 2 P1
This means that the pressure would become double of it's initial pressure.
What does the reaction rate measure?
Answer:
It's C
Explanation:
cuz im goated
How is wind energy more environmental friendly than heat energy?
Answer:
Wind is an emissions-free source of energy
Overall, using wind to produce energy has fewer effects on the environment than many other energy sources. Wind turbines do not release emissions that can pollute the air or water (with rare exceptions), and they do not require water for cooling.
Explanation:
Choose the aqueous solution below with the highest boiling point. These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.
The question is incomplete, the complete question is;
Choose the aqueous solution that has the highest boiling point. These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable. 0.100 m C6H12O6 0.100 m AlCl3 0.100 m NaCl 0.100 m MgCl2 They all have the same boiling point.
Answer:
AlCl3 0.100 m
Explanation:
Let us remember that the boiling point elevation is given by;
ΔTb = Kb m i
Where;
ΔTb = boiling point elevation
Kb = boiling point constant
m = molality of the solution
i = Van't Hoff factor
We can see from the question that all the solutions possess the same molality, ΔTb now depends on the value of the Van't Hoff factor which in turn depends on the number of particles in solution.
AlCl3 yields four particles in solution, hence ΔTb is highest for AlCl3 . The solution having the highest value of ΔTb also has the highest boiling point.