The Bohr radius of a hydrogen atom is 0.0000000000529. Express the Bohr radius of a hydrogen atom in scientific notation. (1 point)

Question

O 5.29 × 108
• 5.29 × 10-13
• 5.29 × 10-11
O 5.29 × 1011

Answer 1

The Bohr radius of a hydrogen atom is given as \(0.0000000000529\). To express this in scientific notation, we can rewrite it as follows:

1. Move the decimal point to the right until we have a number between 1 and 10. Here, we would move the decimal point 11 places to the right, resulting in \(5.29\).
2. Since we moved the decimal point 11 places to the right, we must use a negative exponent for 10.

Thus, the Bohr radius in scientific notation is:

\[ 5.29 \times 10^{-11} \]

So the correct answer is:

• \(5.29 \times 10^{-11}\)

Answer 2

The average weight of a blue whale is 4 × 105 pounds. The average weight of an elephant is 1 × 10* pounds. Approximately how many times heavier is a blue whale than an elephant in pounds?
Hint: You can change both of these to the number without scientific notation if that helps.
(1 point)
4 times heavier.
2 times heavier.
40 times heavier.

Answer 3

To compare the weights of a blue whale and an elephant, let's first express both weights in standard form:

• The average weight of a blue whale is given as \(4 \times 10^5\) pounds. This is equal to: \[ 4 \times 100000 = 400000 \text{ pounds.} \]

• The average weight of an elephant is given as \(1 \times 10^* \) pounds. However, it seems like the exponent is missing. If we assume the average weight of an elephant is \(1 \times 10^4\) pounds (which is a common approximate weight for an elephant), that would equal: \[ 1 \times 10000 = 10000 \text{ pounds.} \]

Now, we can find out how many times heavier a blue whale is than an elephant by dividing the weight of the blue whale by the weight of the elephant:

\[ \text{Times heavier} = \frac{\text{Weight of blue whale}}{\text{Weight of elephant}} = \frac{400000}{10000} = 40. \]

Thus, a blue whale is approximately 40 times heavier than an elephant.

So the correct answer is:

40 times heavier.