Calculate the product of 0.0002115m and 0.405m. express the answer in scientific notation

0.0002115 times 0,0000405=0,0000000085657 and 0.0000000085657 in scientific notation is 8.5657 times 10 to negative 9'th power

Explanation:you have to count from 7  the 5 and place the decimal between the 8 and the 5

percent abundance for cu-63 can be shown as:

63 x + 65 (1-x) = 62.9296

65 - 62.9296 = 2 x

x = 1.035

thus, percent abundance for cu-63 is 1.035

percent abundance for cu-65 can be shown as:

63 x + 65 (1-x) = 64.9278

65 - 64.9278 = 2 x

x = 0.0361

thus, percent abundance for cu-63 is 0.0361

the mass spectrum of cu-63 showing the intense peak as, this isotope is found in nature more abundantly around 92.38 % in comparison to cu-65 which is found 62.58 % naturally