the mass of a benzene molecule is 1.3×10⁻²² grams. the mass of an electron is 9.11×10⁻²⁸ grams. how many…

Explanation:

Step1: Set up the division

To find out how many times greater the mass of a benzene molecule is than the mass of an electron, we divide the mass of the benzene molecule by the mass of the electron. Let $m_b$ be the mass of the benzene - molecule ($m_b = 1.3\times10^{-22}$ g) and $m_e$ be the mass of the electron ($m_e=9.11\times 10^{-28}$ g). The ratio $r=\frac{m_b}{m_e}=\frac{1.3\times 10^{-22}}{9.11\times 10^{-28}}$.

Step2: Use the quotient - rule of exponents

The quotient - rule of exponents states that $\frac{a\times10^m}{b\times10^n}=\frac{a}{b}\times10^{m - n}$. So, $\frac{1.3\times 10^{-22}}{9.11\times 10^{-28}}=\frac{1.3}{9.11}\times10^{-22-(-28)}$. First, calculate $\frac{1.3}{9.11}\approx0.143$. Then, calculate $-22-(-28)=-22 + 28 = 6$. So the result is $0.143\times10^{6}$.

Step3: Convert to standard notation

To convert $0.143\times10^{6}$ to standard notation, we move the decimal point 6 places to the right. $0.143\times10^{6}=143000$. Rounding to the nearest tenth, we get $143000.0$.

Answer:

$143000.0$