Answer:

Explanation:
The atomic number (Z) of copper is 29 and this isotope has an atomic mass (A) of 70.
The general symbol for an isotope E is
.
The atomic number is a left subscript, and the atomic mass is a left superscript.

This info tells us if it stable or not and it tells us how many electrons it need to be stable.
Step 1 : Write balanced chemical equation.
CaF₂ can be converted to F₂ in 2 steps. The reactions are mentioned below.
I] 
II] 
The final balanced equation for this reaction can be written as

Step 2: Find moles of CaF₂ Using balanced equation
We have 1.12 mol F₂
The mole ratio of CaF₂ and F₂ is 1:1

Step 3 : Calculate molar mass of CaF2.
Molar mass of CaF₂ can be calculated by adding atomic masses of Ca and F
Molar mass of CaF₂ = Ca + 2 (F)
Molar mass of CaF₂ = 40.08 + 18.998 = 78.08 g
Step 4 : Find grams of CaF₂
Grams of CaF₂ = 
Grams of CaF₂ = 87.45 g
87.45 grams of CaF2 would be needed to produce 1.12 moles of F2.
A standard solution is a solution (in this case sodium hydroxide) whose concentration (molarity) is known very precisely. <span>The molarity of the sodium hydroxide solution cannot be determined accurately because s</span>olid sodium hydroxide is highly hygroscopic (absorbs water from the air) and cannot be accurately weighed. Sodium hydroxide form sodium carbonate because it absorbs carbon
dioxide from the air.
First I would have a pot of soil and a carrot (without fertilizer) then a pot of soli ,with fertilizer and a carrot. Then I would watch them for the same amount of time and identify weather the soil impacted the decomposition of the carrot and repeat this twice.
Same size pots
Same size carrots
Same soil
Same growth area