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3 years ago

Select the correct answer.

Chemistry

2 answers:

geniusboy [140]3 years ago

7 0

Answer:

The source of the activation energy needed to push reactions forward is typically heat energy from the surroundings.

Explanation:

The activation energy of a particular reaction determines the rate at which it will proceed. The higher the activation energy, the slower the chemical reaction will be

Sloan [31]3 years ago

3 0

The correct answer is c

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Chem !! 15 pts + brainliest

evablogger [386]

Answer:

V = 80.65L

Explanation:

Volume = ?

Number of moles n = 5 mol

Temperature (T) = 393.15K

Pressure = 1520mmHg

Ideal gas constant (R) = 62.363mmHg.L/mol.K

According to ideal gas law,

PV = nRT

P = pressure of the ideal gas

V = volume the gas occupies

n = number of moles of the gas

R = ideal gas constant (note this can varies depending on the unit of your variables)

T = temperature of the ideal gas

PV = nRT

Solve for V,

V = nRT / P

V = (5 * 62.363 * 393.15) / 1520

V = 80.65L

The volume the gas occupies is 80.65L

3 0

3 years ago

What is the pressure of 1.20 moles of SO2 gas in a 4L container at 30 degrees celsius

geniusboy [140]

Let suppose the Gas is acting Ideally, Then According to Ideal Gas Equation,

P V = n R T
Solving for P,
P = n R T / V ----- (1)
Data Given;

Moles = n = 1.20 mol

Volume = V = 4 L

Temperature = T = 30 + 273 = 303 K

Gas Constant = R = 0.08206 atm.L.mol⁻¹.K⁻¹

Putting Values in Eq.1,

P = (1.20 mol × 0.08206 atm.L.mol⁻¹.K⁻¹ × 303 K) ÷ 4 L

P = 7.45 atm

6 0

3 years ago

Read 2 more answers

A sample of CaCO3 (molar mass 100. g) was reported as being 30. percent Ca. Assuming no calcium was present in any impurities, c

natka813 [3]

Answer:

Approximately 75%.

Explanation:

Look up the relative atomic mass of Ca on a modern periodic table:

Ca: 40.078.

There are one mole of Ca atoms in each mole of CaCO₃ formula unit.

The mass of one mole of CaCO₃ is the same as the molar mass of this compound: $\rm 100\; g$ .
The mass of one mole of Ca atoms is (numerically) the same as the relative atomic mass of this element: $\rm 40.078\; g$ .

Calculate the mass ratio of Ca in a pure sample of CaCO₃:

$\displaystyle \frac{m(\mathrm{Ca})}{m\left(\mathrm{CaCO_3}\right)} = \frac{40.078}{100} \approx \frac{2}{5}$ .

Let the mass of the sample be 100 g. This sample of CaCO₃ contains 30% Ca by mass. In that 100 grams of this sample, there would be $\rm 30 \% \times 100\; g = 30\; g$ of Ca atoms. Assuming that the impurity does not contain any Ca. In other words, all these Ca atoms belong to CaCO₃. Apply the ratio $\displaystyle \frac{m(\mathrm{Ca})}{m\left(\mathrm{CaCO_3}\right)} \approx \frac{2}{5}$ :

$\begin{aligned} m\left(\mathrm{CaCO_3}\right) &= m(\mathrm{Ca})\left/\frac{m(\mathrm{Ca})}{m\left(\mathrm{CaCO_3}\right)}\right. \cr &\approx 30\; \rm g \left/ \frac{2}{5}\right. \cr &= 75\; \rm g \end{aligned}$ .

In other words, by these assumptions, 100 grams of this sample would contain 75 grams of CaCO₃. The percentage mass of CaCO₃ in this sample would thus be equal to:

$\displaystyle 100\%\times \frac{m\left(\mathrm{CaCO_3}\right)}{m(\text{sample})} = \frac{75}{100} = 75\%$ .

3 0

3 years ago

T or F: Lone pairs around the oxygen atom of a water molecule play no role in determining its molecular geometry?

Mama L [17]

Answer:

Explanation:

They play a very important part. The geometry is not a straight line. It is an angle over 90 which means that the molecule has the same general shape as a boomerang. The two hydrogens and the 2 lone electron pairs try to get away as far as possible from each other. The actual shape results in a tetrahedron shape. But the two hydrogens and 1 oxygen actually look like the aforementioned boomerang.

5 0

2 years ago

What is the result of cell division that includes mitosis?

tamaranim1 [39]

Answer:

I think C is the answer

Explanation:

because Mitosis results in two identical daughter cells......

5 0

2 years ago