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Would freezing liquid mercury be considered a physical or chemical change?

Would freezing liquid mercury be considered a physical or chemical change?

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Would freezing liquid mercury be considered a

physical or chemical change?

physical

Would dissolving sodium chloride in water be

considered a physical or chemical change?

physical

What are the two categories of pure substances?

Elements and compounds

How can an element be further separated? By

ordinary physical means; By ordinary chemical means; Or it cannot be further separated

by ordinary physical or chemical means.

Cannot be separated by ordinary physical or

chemical means

As what type of matter would you classify vinegar?

Homogeneous mixture

At one point in the school year, our room was a

comfortable 85°F. Is this observation qualitative or

quantitative?

quantitative

A group of measurements that closely agree with one

another but are far from the “true” value are said to be…

precise

How many sig figs are in the following measurement:

0.0390060

6 sf

Object A has a mass of 15.2 g and a volume of 3.6 mL.

Object B has a volume of 4.1 mL and a mass of 16.8 g. Which will sink first in

water?

Object A (4.22g/mL vs. B= 4.10g/mL

You are in the lab and need to mix hydrochloric acid and

water. In what order should you do this?

Pour acid into water

Which subatomic particle has a mass so small that it

is considered negligible when finding mass

number?

electron

An unknown element has 38 protons, 36 electrons, and 50

neutrons. Identify the element.

Always use protons for identity

Strontium (*Sr2+)

Isotopes occur when atoms of the same element have

different mass numbers. Therefore, an isotope has the

same # of ______, but a different # of ______.

Same = protons

Different = neutrons

An atom has an atomic # of 31 and a mass # of 70. How

many protons, electrons, and neutrons does the atom have?

Protons = 31

Electrons = 31

Neutrons = 39

What family has an electron configuration

that ends in p5?

Halogens

What is the Noble Gas configuration

for Tungsten?

[Xe]6s14f145d5

How many electrons can be held in each energy level

(n=1-4) of the atom?

n = 1 2e- (s)

n = 2 8e- (s, p)

n = 3 18e- (s, p, d)

n = 4 32e- (s, p, d, f)

Calculate the wavelength of a photon with an energy of

1.66x10-20 kJ.

J = 1.66x10-17 J

V = 2.5 x1016 Hz

Wavelength = 1.2 x10-8 m

Do metals generally form

cations or anions?

cations

Give the group and period trend for atomic radius.

Decreases across a period, increases down a column.

What type of elements tend to form covalent/molecular bonds?

2 nonmetals

Which molecule is nonpolar:

BH3 or PH3?

BH3

According to VSEPR theory, what is the molecular geometry

of the compound chlorine pentafluoride ?

Square pyramidal

What type of bond is likely to form between two atoms with the

same electronegativity value?

A nonpolar covalent bond

When comparing single, double and triple covalent bonds, a single covalent bond has the

____ bond length and the _____ bond enthalpy.

Single Covalent Bond

Longest – bond length

Lowest/weakest – bond enthalpy

What is the correct name for

Mn(CrO4)2?

Manganese (IV) chromate

What is the correct name for C3H8?

Tricarbon octahydride

What is the correct formula for ammonium sulfite?

(NH4)2SO3

A compound contains 47.0% K, 14.5% C, and 38.5 % O. Its molecular weight is 166.22

g/mol. What is its molecular formula?

K2C2O4

If aqueous solutions of strontium chloride and sodium sulfate are

mixed together, will a precipitate form?

Yes, strontium sulfate is insoluble (s)

What do we call the ions that appear in identical forms among

both the reactants and products of a complete ionic equation that are

not written in the net ionic equation?

Spectator ions

Classify and balance the reaction below:

__ K3PO4 + __CdCl2 __KCl + __Cd3(PO4)2

Double Replacement

2 K3PO4 + 3 CdCl2 6 KCl + 1 Cd3(PO4)2

In the balanced combustion reaction of ethane (C2H6), oxygen has the stoichiometric coefficient

of ____.

Seven

2 C2H6 + 7 O2 4 CO2 + 3 H2O

Complete the single replacement reaction below?

__ Cu (s) + __ Li3N (aq)

No Reaction, Cu is below Li on the activity series

What is the molar mass of magnesium nitrate?

Mg(NO3)2 = 148.33 g/mol

How many moles of pyridine (C5H5N) are contained in 3.13g

of pyridine?

0.0396 moles

In an experiment, a 0.33 mole sample of N2 reacts completely.

What is the mass of Mg consumed in the reaction?

3 Mg + N2 Mg3N2

24.07 g Mg

In an experiment, the reaction of 4.73g of Mg with 1.83g of H2O actually produced 0.095g of H2. What is the percent yield of this

reaction?

Mg (s) + 2 H2O (l) Mg(OH)2 (s) + H2 (g)

92.23% yield