The answer is (3) 53.5 g/mol. The gram formula mass means that the mass of one mol compound. 1N=14, 4H=4, 1Cl=35.5. So the gram formula mass of NH4Cl=14+4+35.5=53.5 g/mol.
PH = -log10 [H+]. So anwer 2 pH
Answer:
Approximately 
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Explanation:
Look up the specific heat of gaseous neon:
.
Calculate the required temperature change:
.
Let 
denote the mass of a sample of specific heat 
. Energy required to raise the temperature of this sample by 
:
.
For the neon gas in this question:
Calculate the energy associated with this temperature change:
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We can use a ratio to solve this question. Lets refer to the amount formed by the formula as a serving
1 serving needs 3/8 gal
We want to create 7/9 servings extra, so
1 + 7/9 = 16/7
1 : 3/8
16/7 : x
1/(3/8) = (16/7) / x
8 / 3 = 16x / 7
x = 7/6
He needs to use 7/6 gallons of water.
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