Test 2 Practice Chem B H 2021

What volume of hydrogen gas will be produced at STP by the reaction 67.3 g of magnesium with excess water according to the following reaction?

Mg + 2H₂O --> Mg(OH)₂ + H₂

• 62.0 L

• 5.54 L

• 67.0 L

• 124 L

How many moles of oxygen gas are in 50.0L of a sample at STP?

• 2.23 mol

• 71.4 mol

• 22.4 mol

• 1120 mol

Zn +2HCI→ ZnCI₂ + H₂

If 0.30 mol Zn reacts with excess HCI, what volume of H₂ will be formed at STP?

• 0.013 L

• 22.4 L

• 6.7 L

• 0.10 L

If I have 5.6 liters of gas in a piston at a pressure of 1.5 atm and compress the gas until its volume is 4.8 L, what will the new pressure inside the piston be?

• 1.8 atm

• 3.27 atm

• 1.8 L

• 3.27 atm

A sample of nitrogen occupies a volume of 250 mL at 25^oC. What volume will it occupy at 95^oC?

• 308.70 mL

• 456.1 mL

• 308.70^oC

• 456.1^oC

A rigid plastic container holds 1.00 L methane gas at 0.9 atm pressure when the temperature is 22.0°C. How much more pressure will the gas exert if the temperature is raised to 44.6°C?

• 0.97 atm

• 1.82 atm

• 0.97^oC

• 1.82^oC

If a gas sample has a pressure of 30.7 kPa at 0.00°C, by how much does the temperature have to decrease to lower the pressure to 28.4 kPa?

• 33.89 ^oC

• -20.46 ^oC

• 597 ^oC

• -4.25 ^oC

As we dilute a solution.....

• The volume increases and the molarity (M) increases

• The volume increases and the molarity (M) decreases

• The volume decreases and the molarity (M) increases

• The volume decreases and the molarity (M) decreases

How many mL of stock solution of 2M NaCl do you need to prepare 100 mL of 0.150M NaCl?

• 7.5 mL

• 15 mL

• 1333 mL

• 200 mL

Calculate the Molarity in a solution containing 40.0 g of NaCl dissolved in 500.0 ml of H2O.

• 0.08 M

• 12.5 M

• 1.37 M

• 0.74 M