1 Standard temperature and a pressure of 0.5 atmosphere are equal to

(1) 0C and 380 torr          (3) 0C and 760 torr
(2) 32C and 380 torr       (4) 32C and 760 torr

1         2         3         4        

2 An atom of fluorine has a mass of 19 atomic mass units. The total number of protons and neutrons in its nucleus is

(1) 9           (3) 19
(2) 10         (4) 28

1         2         3         4        

1         2         3         4        

4 What is the atomic number of an element that has six protons and eight neutrons?

(1) 6         (3) 8
(2) 10       (4) 14

1         2         3         4        

5 Which statement about the mass of an electron is correct?

(1) The mass of an electron is equal to the mass of a proton.
(2) The mass of an electron is less than the mass of a proton.
(3) The mass of an electron is equal to the mass of a neutron.
(4) The mass of an electron is greater than the mass of a neutron.

1         2         3         4