chem review

Sig/figs

100

How many sig figs in 167

3

200

How many sig figs in 3,000,000

1

300

How many sig figs in 367.000

6

400

How many sig figs in 0.000000002

1

500

How many sig figs in 0.003400

4

sci notation

100

Change into scientific notation

54,000,000

5.4x10⁷

200

Change into scientific notation

0.000005767

5.767x10^-6

300

Add

(5.37x10⁵)+(6.67x10⁷)

6.7237x10⁷

400

Multiply

(2.56x10^-7) X (7.89x10⁹)

2.02x10³

500

Divide

(3.14X10⁴) / (7.98x10⁷)

3.93x10^-4

Atoms/History

100

What are the 3 subatomic particles of an atom and what are their charges

Protons, Neutron, Electrons

+             0             -

200

Who conducted the cathode ray experiment?

What was discovered?

JJ Thompson

Electrons

300

Who conducted the gold foil experiment?

What was discovered? (2 things)

Ernest Rutherford

The nucleus was discovered

Also the atom is mostly empty space

400

Give the definition of atomic mass, mass number, atomic number, isotope

Weighted average of the mass of isotopes

Protons plus neutrons

Number of protons

Atoms with same number of neutrons but different number of protons

500

What's the difference between mass number and atomic mass? (must use isotope in the answer)

Also, how many electrons does a neutral atom have given the number of protons

Mass number refers to the number of protons and neutrons of a specific isotope

Atomic mass is the average mass of the isotopes

In a neutral atom, the number of electrons equal the number of protons

Ions

100

What is an ion? Cation? Anion?

An ion is an atom with a charge (charged)

Cation is positive charge

Anion is negative charge

200

What makes an atom have a neutral charge?

When the protons and electrons are equal, the positive and negative charges cancel out giving a neutral charge (overall charge of 0)

300

What's the overall charge of an atom that has 67 protons and 63 electrons

4+

400

If an atomic has a charge of 67+ and has 167 protons, how many electrons does the atom have?

100 electrons

500

If an atom has a charge of 4-, and the atomic number is 35, how many electrons does this atom have. Also what atom is this (you may look at the periodic table)

39 electrons

Bromine

Atomic Mass Calculation/Dim Analysis

100

Convert 35.45 inches to centimeters given 1 inch = 2.54 cm

90.043 cm

200

Convert 300,000 seconds to weeks

0.496 weeks

300

Calculate the atomic mass of chlorine if the two common isotopes of chlorine have masses of 35.45 amu (75.00% abundance) and 37.29 amu (25.00% abundance).

35.91 amu

400

Calculate the atomic mass of one of indium’s isotopes (there are two) if the atomic mass of indium is 114.8200 amu and one isotope of indium has a mass of 114.9041 amu and an abundance of 95.795%.

112.9 amu

500

Convert 2,500 km to miles

(must show perfect proper work)

1553.4 miles