Multiple Choice
The element X has three naturally occurring isotopes. The masses (amu) and % abundances of the isotopes are given in the table below. The average atomic mass of the element is ________ amu. 
A) 219.7
B) 220.4
C) 220.42
D) 218.5
E) 221.0
Correct Answer:

Verified
Correct Answer:
Verified
Q18: What is the molecular formula for pentane?<br>A)C<sub>2</sub>H<sub>8</sub><br>B)C<sub>3</sub>H<sub>6</sub><br>C)C<sub>4</sub>H<sub>8</sub><br>D)C<sub>5</sub>H<sub>12</sub><br>E)C<sub>5</sub>H<sub>10</sub>
Q19: In the symbol shown below, x =
Q26: There are _ protons, _ neutrons, and
Q41: All atoms of a given element have
Q83: Calcium forms an ion with a charge
Q168: The formula for zinc phosphate is Zn<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub>.What
Q180: Of the following,the smallest and lightest subatomic
Q206: Predict the empirical formula of the ionic
Q232: The correct name for H<sub>2</sub>CO<sub>3</sub> is _.<br>A)carbonous
Q237: Which pair of elements would you expect