Silicon, Which Makes Up About 25% of Earth's Crust by Mass

question 18

Multiple Choice

Silicon, which makes up about 25% of Earth's crust by mass, is used widely in the modern electronics industry. It has three naturally occurring isotopes, ²⁸Si, ²⁹Si, and ³⁰Si. Calculate the atomic mass of silicon.

• A) 29.2252 amu
• B) 28.9757 amu
• C) 28.7260 amu
• D) 28.0855 amu
• E) 27.9801 amu

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Definitions:

Common Stock

A type of equity security that represents ownership in a corporation, giving holders voting rights and a share in the company’s profits via dividends.

Authorized Shares

The maximum number of shares that a corporation is legally allowed to issue, as specified in its articles of incorporation.

Reacquired Shares

Shares that a company buys back from its shareholders, reducing the amount of outstanding stock on the market.

Par Common Stock

The nominal or face value assigned to common shares in the articles of incorporation, often having little relation to the market value.