Answer:
20.0928.
Explanation:
The average atomic mass is (90 * 19.992 + 10* 21) / 100
= 20.0928.
Answer:
14.93 g
Explanation:
First we <u>convert 1.2 x 10²³ atoms of arsenic (As) into moles</u>, using <em>Avogadro's number</em>:
- 1.2 x 10²³ atoms ÷ 6.023x10²³ atoms/mol = 0.199 mol As
Then we can<u> calculate the mass of 0.199 moles of arsenic</u>, using its<em> molar mass</em>:
- 0.199 mol * 74.92 g/mol = 14.93 g
Thus, 1.2x10²³ atoms of arsenic weigh 14.93 grams.
Answer:
Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century, most gulls were placed in the genus
Answer:
The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. The mass number is different for each different isotope of a chemical element.
