I would say D. Let me know if i am wrong.
3.9 grams CaCO3
The mass of 2.0 L of water with a density of 1.00 g/ml is 2000 grams.And 1 ppm of that is 2000 / 1000000 = 0.002 grams. So just multiply by the ppm of CaCO3, giving 0.002 g * 1.95x10^3 = 3.90 grams.
Since the least accurate datum we have is 2 significant figures, the result should be rounded to 2 significant figures, giving 3.9 grams.
Neutral, because anything too acidic or basic would kill a person
Answer:
See explanation
Explanation:
a) Isotopes are variants of one chemical element which (such as Nitrogen in this case). Those variants differ in <u>neutron number</u> and <u>nucleon number</u>.
This is also the reason why they have <u>different masses</u>. Isotopes are different physically to their original atoms.
b) All isotopes of a given element have the same number of protons and electrons. All the isotopes have the same atomic number as the original element. Isotopes are almost the same chemically.
c) The 14 in the name of Nitrogen-14, means it has a mass of 14u ( while Nitrogen 15 has a mass of 15 u). Nitrogen-14 will have the greatest affect on the average atomic mass, this because of the 95% abundance.
Nitrogen has an average atomic mass of 14.0067 u. This is the closest to 14, what shows nitrogen-14 has the biggest affect.
The average atomic mass is calculated as following: 14*0.95 +15*0.03 + 16*0.02 =14.07 u
d) Both are isotopes, but of another element. They both have a mass of 14 u. Bu they have a different number of neutrons: Oxygen-14 has 6 neutrons and 8 protons while Nitrogen-14 has 7 neutrons and 7 protons. This means oxygen-14 and nitrogen-14 are not isotopes, since isotopes do have the same number of neutrons.