Answer:
When a number is written in scientific notation, the exponent tells you if the term is a large or a small number. A positive exponent indicates a large number and a negative exponent indicates a small number that is between 0 and 1.
Answer:
1 g
Explanation:
The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.
We can make a table of the mass left after each half-life.

The mass remaining after 48 h is 1 g.
Answer:
14 gallons
Explanation:
357 divided by 14 = 25.5 and if you check your answer 14 x 25.5 = 357 (i hope this is right)
The answer to that is mass and chemical
<h2>Answer:</h2>
He is right that the energy of vaporization of 47 g of water s 106222 j.
<h3>Explanation:</h3>
Enthalpy of vaporization or heat of vaporization is the amount of energy which is used to transform one mole of liquid into gas.
In case of water it is 40.65 KJ/mol. And 18 g of water is equal to one mole.
It means for vaporizing 18 g, 40.65 kJ energy is needed.
So for energy 47 g of water = 47/18 * 40.65 = 106.1 KJ
Hence the student is right about the energy of vaporization of 47 g of water.