the amount of fluorine in a metal fluoride is 14.96%. 2 Chromium are connected to the metal when metal chromate is formed. What is the relative atomic mass of the metal

The relative atomic mass of the metal is  207.2 u

Explanation:

Metal chromate

Given that;

1) The mass of fluorine is 14.96% of the metal fluoride

2) 2 Chromium are connected to the metal when the metal chromate, CrO²⁻, is formed

We have;

Number of ions available in the metal =  Cr₂O₇²⁻ = +2 ionic

Molar mass of fluorine = 18.998 g/mole

Ionization of fluorine = -1

Number of moles of fluorine required per metal +2 ion= 2 moles

3) Number of moles of fluorine per mole of compound of the metal fluoride = 2 × moles

Mass of fluorine per mole of compound = 2 × 18.998 = 37.996 grams

Percentage by mass of fluorine = 14.96%

Fluoride

Let the mass of the compound = X

Therefore;

14.96% of X = 37.996 grams

X = 37.996/(0.1496) = 253.984 grams

Therefore the mass of the metal in the compound = 253.984 - 37.996 = Molar mass 215.99 grams

Given that the metal forms a chromate with 2 chromium atoms and a mass of 215.99 grams, the likely candidate is lead, Pb with a molar mass of 207.2 grams and a chromate of Pb(CrO₄)₂.

The fluoride, lead fluoride, F₂

The relative atomic mass of lead is 207.2 u

take a better picture and ill do it

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.