What is the atomic mass of an element if 4.00 grams of it contains 2.98x10^22 atoms

The molar mass of the element is 80.8 g/mol

Explanation:

We are given:

Number of atoms =

According to mole concept:

number of atoms are contained in 1 mole of an element

So, number of atoms will be contained in of an element

To calculate the molar mass for given number of moles, we use the equation:

Given mass of element = 4.00 g

Moles of an element = 0.0495 moles

Putting values in above equation, we get:

Hence, the molar mass of the element is 80.8 g/mol

a: 45.9 meters

b: 4.29 seconds

step-by-step explanation:

a: h(t)=1/2(-9.8)(3)^2+0(3)+90

h(t)=-4.9(3)^2+90

h(t)=-44.1+90

h(t)=45.9 meters

b: 0=1/2(-9.8)(t^2)+0t+90

0=-4.9t^2+90

-90=-4.9t^2

18.37=t^2

t=4.29 seconds

in the second question, the numbers aren't exact, but they're a close approximation.