Full Question:
Ammonia chemically reacts with oxygen gas to produce nitric oxide and water. What mass of water is produced by the reaction of 7.7g of ammonia?
Be sure your answer has the correct number of significant digits.
Answer:
12.23g ≈ 12g (2 s.f)
Explanation:
Ammonia chemically reacts with oxygen gas to produce nitric oxide and water. The balanced chemical reaction is given as:
4 NH3 + 5 O2 -------> 4 NO + 6 H2O
From the reaction;
4 mole of ammonia reacts to produce 6 moles of water
From the question;
Moles = mass / molar mass
From the question;
moles of ammonia = mass / molar mass = 7.7 / 17 = 0.4529moles
Number of moles of water produced;
4 = 6
0.4529 = x
x = (0.4529 * 6 ) / 4
x = 0.67935moles
Mass of water = moles * molar mass = 0.67935 * 18 = 12.23g ≈ 12g (2 s.f)
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
I was going to help but I don’t understand the question
Answer:

Explanation:
Hello,
In this case, the first step is to compute the difference in the electronegativity for the formed bond between gallium and phosphorous by:

Thus, we can compute the percentage of ionic character by:

So the fraction is just:

Which has sense since gallium phosphide is a non-polar compound.
Regards.
Answer:
Average density of the liquid = 0.992 g/mL
Explanation:
Density = mass/volume
mass of liquid = (mass of liquid + mass of cylinder) - mass of cylinder
Trial 1: mass of liquid = 19.731 - 9.861 = 9.87
volume of liquid = 10 mL
density of liquid = 9.87 g / 10 mL = 0.987 g/mL
Trial 2: mass of liquid = 19.831 - 9.861 = 9.97
volume of liquid = 10 mL
density of liquid = 9.97 g / 10 mL = 0.997 g/mL
Trial 3: mass of liquid = 19.831 - 9.861 = 9.97
volume of liquid = 10 mL
density of liquid = 9.97 g / 10 mL = 0.997 g/mL
Trial 4: mass of liquid = 19.771 - 9.861 = 9.91
volume of liquid = 10 mL
density of liquid = 9.91 g / 10 mL = 0.991 g/mL
Trial 5: mass of liquid = 19.751 - 9.861 = 9.89
volume of liquid = 10 mL
density of liquid = 9.89 g / 10 mL = 0.989 g/mL
Average density = (0.987 + 0.997 + 0.997 + 0.991 + 0.989)/5 = 4.961/5
Average density of the liquid = 0.992 g/mL