Scientists often repeat one or more steps several times.
Melamine should be the right answer, i hope this helps.
126 grams of H2O is formed.
Explanation:
Data given:
volume of the gas = 88 Liters
pressure = 720 mm Hg or 0.947 atm
temperature T = 22 Degrees or 295.15 K
R = 0.08021 atm L/mole K
n =?
The formula is used is of ideal gas law to know the number of moles of CH4 undergoing combustion.
PV = nRT
n = 
putting the values in the equation
= 0.947 X 88/ 0.08021 X 295.15
n = 3.5 moles
balanced reaction for combustion of methane
CH4 + O2 ⇒ CO2 + 2H20
1 mole of CH4 undergoes combustion to form 2 moles of water
3.5 moles will give x moles of water
2/1 = x/3.5
x = 7 moles of water (atomic mass of water = 18 gram/mole)
mass = atomic mass x number of moles
mass = 18 x 7
=126 grams of water is formed.
Explanation:
Given that,
Volume of a hallow glass sphere is 350 mL
Specific gravity is 1.252
We need to find the weight of the sphere. The ratio of density of substance to the density of water is called specific gravity.
The density of water is 1 g/mL

We know that,
1 pound = 453.592 grams
So,
m = 0.97 lbs
So, the weight of the sphere is 0.97 lbs or 0.97 pounds.