Chapter two

Question 1

Define nucleus

Answer 1

The positively charged center of an atom, containing nearly all of the atom’s mass. The nucleus contains protons and neutrons.

Question 2

What is the force that holds together a proton and a neutron

Answer 2

A strong nuclear force is what holds protons and neutrons together

Question 3

What is an amu equal to

Answer 3

one amu is 1/12 of a carbon atom

Question 4

What else is an amu known as?

Answer 4

An amu is also known as a Dalton (Da) named after the English chemist John Dalton

Question 5

What is Francis Aston’s positive-ray analyzer

Answer 5

This is a machine that found that there are two different isotopes for certain elements. They found this out because they found that some atoms of the element wouldn’t get shot as far this is because they were heavier.

Question 6

Define an Isotope

Answer 6

atoms of an element containing the same number of protons but in a different number of neutrons.

Question 7

Define average atomic mass

Answer 7

Weighted average of masses of all isotopes of an element, this is calculated by multiplying the natural abundance of each isotope by its mass in amu and then summing these products.

Question 8

Define natural abundance

Answer 8

Proportion of a particular isotope; usually expressed as a percentage relative to all the isotopes for that element in a natural sample

Question 9

What was Mendeleev’s periodic table

Answer 9

This was created by Dmitri Mendeleev, he order the elements by their atomic mass, arranging them into columns based on similar chemical and physical properties. This was the very first primitive periodic table

Question 10

What are the rows and columns called in the modern periodic table

Answer 10

Rows are called periods
Vertical columns are called groups

Question 11

What are the three main categories of the periodic table?

Answer 11

Metals
nonmetals
metalloids

Question 12

What is the law of multiple proportions?

Answer 12

the ratio of the two masses of one element that reacts with a given mass of another element to form two different compounds is the ratio of two small whole numbers

Question 13

Define molecular compounds

Answer 13

atoms held together in molecules by covalent bonds
COMPOSED OF NONMETALS

Question 14

Define covalent bonds

Answer 14

a bond between two atoms created by sharing one or more electrons

Question 15

What’s the difference between a molecular formula and empirical formula

Answer 15

Molecular formula: this shows the number and type of atoms present in one molecule of a compound
Empirical formula: shows the smallest whole-number ratio of the elements in a compound

Question 16

What is a cation

Answer 16

An ion with a positive charge

Question 17

What is an anion

Answer 17

An ion with a negative charge

Question 18

What is an ionic compound?

Answer 18

They are made of metal and nonmetals
Metals form cations
nonmetals form anions

Question 19

Define formula unit?

Answer 19

Smallest electrically neutral unit of an ionic compound

Question 20

What are the rules for naming a molecular compound

Answer 20

the first word is the name of the first element, the second word you change the ending to IDE, and use prefixes to indicate the number of atoms of each atom

Question 21

What are the naming rules for iconic compounds

Answer 21

first use the metals full name, followed by the nonmetal adding IDE as a suffix. NOTE the overall charge must equal zero

Question 22

What is the naming rules for polyatomic ions

Answer 22

The name is based on the name of the element that first appears in the formula. The last part. Not the ending could be ITE, IDE or ATE

Question 23

Whats the naming rules for acids

Answer 23

Binary acids contain hydrogen and a monoatomic anion. The prefix is “hydro” then the halogen base name followed by the suffix “ic” however if the name ends in ITE the acid ending is OUS

Question 24

What are the three types of organic compounds based on bonds?

Answer 24

1:Alkanes
2:Alkenes
3:Alkynes