can someone help, please ??
Chemistry
9. The molecular mass of sodium oxide (Na2O) is
A. 61.97894.
B. 22.98977.
C. 38.98917.
D. 45.97954.
10. A substance that contains hydrogen that may be replaced by a metal is a/an
A. colloid.
B. acid.
C. nonmetal.
D. base