1.326 grams of NH3 are required to produce 4.65 g of HF.
Step-by-step explanation:
Balanced chemical reaction is written first to know the number of moles taking part in original reaction.
NH3 +3 F2 ⇒3 HF + NF3
Given:
mass of HF = 4.65
First the number of moles of HF in 4.65 grams is calculated by using the formula:
number of moles (n) = 
atomic mass of HF = 20 grams/mole
putting the values in the above equation number of moles can be found.
n = 
= 0.235 moles of HF are given.
From the equation it can be said that:
1 mole of NH3 reacts to form 3 moles of HF
so, x moles of NH3 would react to form 0.235 moles of HF
= 
3x = 0.235
x = 
x = 0.078 moles of NH3 is required.
The moles are converted to mass by applying the formula:
mass = atomic mass X number of moles (atomic mass of NH3 = 17 grams/mole)
putting the values in the formula
mass = 17 X 0.078
mass = 1.326 grams
The question mark is 100. It is a variable if you don't know
Answer: ?=7
Explanation: Use pythagorean theorem
So they need $125 to start a slime business.
To get money Carrie start to sell cupcakes for 0.50 cents
Juanita will be selling cards for $2.25
Juanita is selling cards for $2.25 and she is selling at least 35 of them
Carrie is selling cupcakes for 0.50 cents and the number of cupvakes is three times the number of cards so we will multiply 35 x 3=105 number of cupcakes
Then we will multiply 0.50 cents x 105= $53.2 on the cupcakes.
After that, we will multiply $2.25 x 35 for the cards = 78.5
Finally add them together
78.5
+53.3
---------
$ 131.8
So they will have $131.8 after selling cupcakes and cards.