CHM112 College Chemistry Exam 2 Study Guide

These flashcards cover key concepts related to atomic weight, molar mass, chemical reactions, gas laws, heat transfer, and properties of solutions as presented in the CHM112 College Chemistry course notes.

Where can the atomic weight of an element be found?

In the periodic table.

What are the units of atomic weight?

a.m.u.

How is molar mass defined?

Molar mass is expressed in grams per mole (g/mol).

How do you calculate the molecular weight of a compound?

Add the masses of all atoms in its formula.

What is the molar mass of Aluminum?

26.98 g/mol.

What is the molecular weight of Tin (II) Oxide?

76.0 g/mol.

What conversion factor allows conversion between grams and mols?

The molar mass.

How many grams are in 1.0 mol of Carbon?

12.01 g.

How many mols are in 80.0 grams of SnO?

2.00 mols.

How is the reaction 2Mg + O2 → 2MgO classified?

As a combination reaction.

How is the reaction N2 + 3H2 → 2NH3 classified?

As a combination reaction.

Is the equation N2 + 3H2 → 2NH3 balanced?

Yes.

What is the ratio of moles of Silver Nitrate to Silver Chloride?

1 : 1.

What is the stoichiometric coefficient sequence for balancing Zn + HCl → ZnCl2 + H2?

1 : 2 : 1 : 1.

How many moles of Hydrogen gas are generated from the complete reaction of 2 mols of Zinc?

2 moles.

What does the symbol (aq) indicate in a chemical equation?

That the substance is dissolved in water.

Is the equation 2H2O2(aq) → 3H2O(l) + 2O2(g) balanced correctly?

No.

How many moles of Carbon dioxide are produced from 1 mol of ethane (C2H6)?

4 mol.

How many moles are in 56.7 g of Silver Chloride?

0.396 mol.

What equation is used to calculate an unknown when gas properties are constant?

PV = nRT.

What are the preferred units of temperature for gas quantitative problems?

Kelvin.

What are the preferred units of temperature for heat quantitative problems?

Celsius.

Which equation allows calculation of energy absorbed during temperature rise?

q = mCΔT.

What is the volume of 2.34 mol of CO2 at STP?

52.4 L.

If gas pressure increases, what happens to its volume?

The volume decreases.

What energy is needed to raise the temperature of 100 grams of water by 100°C?

83400 Calories.

What is the energy needed to melt 1 gram of water at 0°C?

Heat of Fusion.

How much energy is needed to melt 123.0 grams of ice?

36480 cal.

What is the movement of particles through a medium down their concentration gradient?

Diffusion.

Does Vs in the equation CsVs = CdVd refer to stock volume for dilution?

True.

Does a dilution have a higher concentration than its original stock solution?

False.

How many grams of Ammonia (NH3) are produced from 345 g of Nitrogen gas?

419 g NH3.

How many moles are in 100.0 grams of NaOH?

2.5 mol.

What is the molarity of a solution made by dissolving 123.0 grams of NaOH in 1 L?

3.075 mol/L.

How much 14 M acid stock is needed to make 5.0 L of 0.10 M dilution?

45 mL.

What is the final volume of a 0.33 M dilution from 0.075 L of 12 M stock?

5.8 L.

What is osmosis?

The diffusion of water.

What is the direction of osmosis in hypotonic media?

Into the vesicle.

What is the direction of diffusion between different NaCl concentrations?

From the right chamber to the left chamber.

What are chemical equations written in terms of?

Particles or moles.

What occurs in a synthesis reaction?

Several compounds transform into one compound.

Do oxidation reactions involve changes in charge or oxidation number?

True.

What is the unit of pressure represented by atm, psi, and kPa?

Pressure.

What is evidence of a chemical reaction?

Change of color.

What is not evidence of a chemical reaction?

Phase change.