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3 years ago

1. Suppose during volleyball practice, you lost 2.0 lbs of water due to sweating. If all of this

Chemistry

1 answer:

Lynna [10]3 years ago

3 0

Answer:

$E=2052.8 kJ$

Explanation:

The energy absorbed by the water is the energy it requires to evaporate. So:

$Heat of .vap= 40.65 kJ/mol$

The moles of water:

$n_w=m_w *\frac{1000g}{2.2lbs}*\frac{1}{M}$

M is the water molecular weight

$n_w=2 lbs *\frac{1000g}{2.2lbs}*\frac{1}{18g/mol}$

$n_w=50.5mol$

The energy absorbed:

$E=n_w*Heat of vap.=50.5mol *40.65 kJ/mol$

$E=2052.8 kJ$

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Use the balanced equation given below to solve the problem that follows: Calculate the mass in grams of water produced along wit

saveliy_v [14]

Answer: 1.98 g

Explanation:

To calculate the moles :

$\text{Moles of solute}=\frac{\text{given volume}}{\text{Molar volume}}$

$\text{Moles of} CO_2=\frac{5.0L}{22.4L}=0.22moles$

The balanced given equation is:

$C_2H_2(g)+5O_2(g)\rightarrow 4CO_2(g)+2H_2O(g)$

According to stoichiometry :

4 moles of $CO_2$ will produce = 2 moles of $H_2O$

Thus 0.22 moles of $CO_2$ will produce= $\frac{2}{4}\times 0.22=0.11moles$ of $H_2O$

Mass of $H_2O=moles\times {\text {Molar mass}}=0.11moles\times 18g/mol=1.98g$

Thus 1.98 g of water is produced along with 5.0 L of $CO_2$ at STP

6 0

3 years ago

What is the difference between a strong base and a weak base?

slamgirl [31]

Answer:

A strong base produces more ions in solution than a weak base.

Explanation:

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3 years ago

How many grams of gas must be released from a 32.0 L sample of CO2(g) at STP to reduce the volume to 16.6 L at STP?

Hoochie [10]

Answer:

30.3 g

Explanation:

At STP, 1 mol of any gas will occupy 22.4 L.

With the information above in mind, we calculate how many moles are there in 32.0 L:

32.0 L ÷ 22.4 L/mol = 1.43 mol

Then we calculate how many moles would there be in 16.6 L:

16.6 L ÷ 22.4 L/mol = 0.741 mol

The difference in moles is:

1.43 mol - 0.741 mol = 0.689 mol

Finally we convert 0.689 moles of CO₂ into grams, using its molar mass:

0.689 mol * 44 g/mol = 30.3 g

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3 years ago

5.50 L of a 0.190 M CaCl2M CaCl2 solution How do you find Grams?

Firdavs [7]

Answer:

115.891

Explanation:

Molarity is equal to moles/liters so to get moles we multiply molarity by liters, after this we multiply the moles by the total atomic weight of the compound to get grams

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3 years ago

A cylinder with a moving piston expands from an initial volume of 0.350 L against an external pressure of 1.90 atm. The expansio

myrzilka [38]

Answer:

1.84 L

Explanation:

Using the equation for reversible work:

$W = -P*(V_{2} - V_{1})$

Where:

W is the work done (J) = -287 J.

Since the gas did work, therefore W is negative.

P is the pressure in atm = 1.90 atm.

However, work done is in joules and pressure is in atm. We can use the values of universal gas constant as a convenient conversion unit. R = 8.314 J/(mol*K); R = 0.0821 (L*atm)/(mol*K)

Therefore, the conversion unit is 0.0821/8.314 = 0.00987 (L*atm)/J

$V_{1}$ is the initial volume = 0.350 L

$V_{2}$ is the final volume = ?

Thus:

(-287 J)*0.00987 (L*atm)/J = -1.9 atm*( $V_{2}$ - 0.350) L

$V_{2}$ = [(287*0.00987)+(1.9*0.350)]/1.9 = (2.833+0.665)/1.9 =1.84 L

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3 years ago