A cold front is the leading edge of a cooler mass of air, replacing at ground level a warmer mass of air, which lies within a fairly sharp surface trough of low pressure.
0.370 mol metal oxide = 55.45 g
<span>1 mol = 55.45/0.370 = 149.86 g </span>
<span>in 1 mol there are 3 mol O = 16 * 3 = 48 g of O </span>
<span>there is 48/149.86 * 100% O in the sample </span>
<span>the sample has 48/149.86 * 0.370 = 0.119 g O</span>
Each isotope has a unique rate of decay, making them suitable for determining the dates of ancient artifacts. The answer is "rate of decay of the isotope."
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Answer:
The approximate mass of beryllium is 9.0045 u.
Explanation:
Given data:
mass of helium= 4.002 u
mass of beryllium which is 2.25 times of mass of helium= ?
Solution:
we will multiply the mass of helium with 2.25 times,
4.002 u × 2.25 = 9.0045 u
so the mass of beryllium atom would be 9.0045 u.