Homework 3 and 4

Question 1

A neutral atom has equal numbers of ______ and electrons.

Answer 1

protons

Question 2

Which statement(s) is/are FALSE?
a. Neutral atoms are made of specific numbers of protons and electrons but the number of neutrons they possess can vary a little bit.
b. All atoms are about the same size.
c. Protons and neutrons repel each other and position themselves far apart inside the atom.
d. The number of protons determines what type of element an atom is

Answer 2

b and c

Question 3

Select all possible answers:
What is contained in the nucleus of an atom?
a. protons
b. neutrons
c. electrons
d. none of the above

Answer 3

a and b

Question 4

An _______ is the smallest particle of an element that has the element’s properties.

Answer 4

atom

Question 5

Select all possible answers:
Which of the following statement(s) about chemical bonding are TRUE?
a. Bonds are formed by valence electrons of interacting atoms
b. Bonding occurs to give both atoms a more stable electron configuration
c. Bonding always involves atoms evenly sharing valence electrons
d. Bonds are permanent attractions that cannot be broken once formed

Answer 5

a and b

Question 6

Valence electrons are the basis of all chemical bonds T/F

Answer 6

True

Question 7

Chlorine has 7 valence electrons. Hydrogen has 1 valence electron. How many hydrogen atoms would form chemical bonds with one chlorine atom?
a. 4
b. 7
c. 1
d. 2

Answer 7

c.1

Question 8

In covalent bonds, atoms ________.
a. Share electrons
b. Transfer electrons
c. Lose electrons
d. Gain electrons

Answer 8

a. Share Electrons

Question 9

Pure water is _________.
a. Acidic
b. Basic
c. Neutral
d. All of the above

Answer 9

c. Neutral

Question 10

Ocean water has a pH of approximately 8.5. That means ocean water is ______.
a. acidic
b. basic
c. neutral

Answer 10

b. basic

Question 11

Assume that you test an unknown solution and find that it has a pH of 7.2. What type of solution is it?

Answer 11

Base

Question 12

What is the pH of a neutral solution?
a. 2
b. 5
c. 7
d. 9

Answer 12

c. 7

Question 13

The diffusion of water molecules across a selectively permeable membrane from an area of higher concentration to an area of lower concentration is called diffusion. T/F

Answer 13

F

Question 14

In an isotonic solution, cells ______.
a. Will stay the same
b. Will swell
c. Will burst
d. Will shrink

Answer 14

a. Will stay the same