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3 years ago

Which of the following statements is true?

Chemistry

1 answer:

eduard3 years ago

5 0

Answer:

Lines of latitude are used to divide Earth into 24 time zones

Explanation:

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Help please chemistry will give brainliest

Jlenok [28]

Answer:

Explanation:

The Ideal Gas Law states that PV=nRT.

Rearrange that into P/n=RT/V.

In this case, the cylinder is rigid so the volume, V, does not change.

Temperature does not change either.

Out of 450 grams of gas, 150 grams leak out. So only 450-150 = 300 grams is left.

n is number of moles which is dependent on mass:

n1/n2 = 450/300 = 3/2

P1/n1 = RT/V = P2/n2

P2 = P1/n1*n2

= 7.2/3*2

= 4.8 atmosphere

6 0

3 years ago

Read 2 more answers

One difference between mixtures and pure substances is that A) mixtures can be physically separated. B) mixtures are made of one

Alborosie

The answer your looking for is a)
-please give me brainliest answer

5 0

2 years ago

Read 2 more answers

5.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the

cupoosta [38]

Answer: Thus ∆H, in kJ/mol, for the dissolution of MgSO₄ is -66.7 kJ

Explanation:

To calculate the entalpy, we use the equation:

$q=mc\Delta T$

where,

q = heat absorbed by water = ?

m = mass of water = ${\text {volume of water}}\times {\text {density of water}}=100.0ml\times 1.00g/ml=100.0g$

c = heat capacity of water = 4.186 J/g°C

$\Delta T$ = change in temperature = $6.70^0C$

$q=100.0g\times 4.184J/g^0C\times 6.70^0C=2803.3J=2.8033kJ$

Sign convention of heat:

When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

The heat absorbed by water will be equal to heat released by $MgSO_4$

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass = 5.11 g

Molar mass = 120 g/mol

Putting values in above equation, we get:

$\text{Moles of }MgSO_4=\frac{5.11g}{120g/mol}=0.042mol$

0.042 moles of $MgSO_4$ releases = 2.8033 kJ

1 mole of $MgSO_4$ releases = $\frac{2.8033 kJ}{0.042}\times 1=66.7kJ$

Thus ∆H, in kJ/mol, for the dissolution of MgSO₄ is -66.7 kJ

3 0

3 years ago

Newtons first law second law and third law <br><br> help

Romashka [77]

Answer:

In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction.

Explanation:

hope this helps

7 0

3 years ago

What is the name of the energy needed to change the structure of matter

anyanavicka [17]

Answer:

Heat fusion

Explanation:

The energy required to change a solid to a liquid is called the heat of fusion.

4 0

2 years ago