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Matter and Energy
Atomic Structure
Bonding
Periodic Table
Mathematics of Chem.
100

When a quantity of electricity is converted to heat, the heat energy produced is measured in...

Calories

100

What is the total number of protons and neutrons in an atom of Se?

79

100

What is the total number of electrons in an Mg +2

ion?

10

100

Beryllium is classified as what in the Periodic Table?

An alkaline earth metal

100

What is the mass of 2.0 moles of nitrogen gas?

56g

200

In a closed system, as the temperature of a liquid increases, the vapor pressure of the liquid...

Increases

200

When an atom goes from the excited state to the ground state, the total energy of the atom...?

Decreases

200

The attraction between molecules of methane in the liquid state is primarily due to...?

van der Waals forces
200

Which group contains the most active metals?

Group 1

200

The approx. percent by mass of potassium in KHCO3 is...?

39%

300

What is the volume of 4.40 grams of CO2 at STP?

2.24 L

300

The total number of orbitals in the 4f sublevel is...?

7

300

Which type of bonding is found in a molecule of HBr?

Polar Covalent

300
The alkaline earth element having the largest atomic radius is found in what period?​
Period 7
300

The density of a gas is 3.00 g/L at STP. What is the gram molecular mass of the gas?

67.2g

400

When the vapor pressure of a liquid in an open container equals the atmospheric pressure, the liquid will...

Boil

400

The amount of energy required to remove the most loosely bound electron from an atom in the gaseous phase is called?

Ionization energy

400

Which type of bond exists between carbon atoms in a diamond?

Covalent

400

In Period 2, the number of elements that are gases at STP is...?

4

400

How many calories of heat are absorbed when 50g of water at 100 degrees C are completely vaporized?

27,000 calories

500

10 grams of oxygen gas is added to 10 grams of nitrogen gas. No energy change occurs. 

Is this sample a mixture or a compound?

What percent of the mass does oxygen make up?

A mixture that is 50% oxygen by mass.

500

Which emission from a radioactive source is NOT affected by an electric field? 

(Gamma, beta, alpha...)

gamma rays

500

A pure substance melts at 38 degrees C and does not conduct electricity in either the solid or liquid phase. The substance is classified as...?

(Ionic, metallic, electrovalent, molecular...)

Molecular

500

All of the elements in Period 3 have a total of 2 electrons in which sublevel?

2s sublevel

500

A solution in which an equilibrium exists between dissolved and undissolved solute must be...?

Saturated