Consider an element Z that has two naturally occurring isotopes with the following percent abundances: the isotope with a mass number of 19.0 is 55.0% abundance and the isotope with a mass number of 21.0 is 45.0 % abundant. What is the atomic mass for element Z
A
20.0 amu

B
20.10 amu

C
19.90 amu

D
40.0 amu

The atomic mass of element Z is 19.90 amu.

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The atomic mass for element Z = 19.90 amu (option C is correct)

Explanation:

Step 1: Data given

Element Z has 2 isotopes:

First isotope: Mass number of 19.0 has a natural abundance of 55.0 %

Second isotope: Mass number of 21.0 has a natural abundance of 45.0 %

Step 2: Calculate atomic mass for element Z

Atomic mass = isotopic mass 1 * natural abundance + isotopic mass 2 * natural abundance

Atomic mass = 19.0 * 0.55 + 21.0 *0.450

Atomic mass = 19.90 amu

The atomic mass for element Z = 19.90 amu (option C is correct)

introduction of a drug directly into the respiratory tract is a form of inhalation administration.

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates