Isotopes, Ions, and Average Atomic Mass

When an atom loses an electron, it becomes ____, also known as a/an ______.

• positive, cation

• negative, anion

When an atom gains an electron, it becomes ____, also known as a/an ______.

• positive, cation

• negative, anion

If X is the symbol for an element, which of the following two symbols represent    isotopes of the same element?     I. ⁷⁷₃₅X  II. ⁷⁷₃₃X  III. ⁸¹₃₇X  IV. ⁸¹₃₅ X

• I and II
• III and IV
• I and IV
• I and III

Tags

NGSS.HS-PS1-8

How many protons does this isotope of titanium have?

• 22

• 26

• 48

• 70

Tags

NGSS.MS-PS1-1

Atoms of the same element that have different mass than expected because they have a different number of neutrons.

• Neutral Atom

• Ion

• Isotope

• Cation

Boron has two isotopes: Boron-10 and Boron-11. Which is more abundant in nature?

• Boron-10

• Boron-11

Four isotopes of lead include lead-204, lead-206, lead-207, and lead-208. The average atomic mass of lead is 207.2. Which isotope of lead is likely to be the most abundant?

• Pb-204

• Pb-206

• Pb-207

• Pb-208

Take a look at the periodic table. What is Sulfur's most abundant isotope in nature?

• Sulfur-32

• Sulfur-33

• Sulfur-34

• Sulfur-35

Tags

NGSS.HS-PS1-8

Calculate the average atomic mass of lithium, which occurs as two isotopes that have the following atomic masses and abundances in nature:

Li-6 at 7.30%

Li-7 at 92.70%

• 6.867 amu

• 6.411 amu

• 6.312 amu

• 6.927 amu

An element has the following natural abundances and isotopic masses:

90.92% abundance with 20 amu

0.26% abundance with 21 amu

8.82% abundance with 22 amu

Calculate the average atomic mass of this element.

• 20.179 amu

• 20.253 amu

• 20.581 amu

• 20.789 amu