1) Chemical equation
16Fe(s) + 3S8(s) ---> 8Fe2S3
2) Molar ratios:
16 mol Fe : 3 mole S8 : 8 mol Fe2S3
3) Convert masses in grams to number of moles
number of moles = mass in grams / molar mass
a) iron, Fe
mass = 3.0 g
atomic mass = 55.845 g/mol
=> number of moles of Fe = 3.0g / 55.845 g/mol = 0.0537 mol
b) Sulfur, S8
mass = 2.5 g
molar mass = 8*32.065 g/mol = 256.52 g/mol
=> number of moles of S8 = 2.5g / 256.52 g/mol = 0.009746 mol
4) Limiting reactant
Theoretical ratio actual ratio
16 mol Fe / 3 mol S8 0.0537 mol Fe / 0.009746 mol S8
5.33 5.50
So, there is a little bit more Fe than the theoretical needed to react all the S8, which means the S8 is the limiting reactant.
5) Calculate the number of moles of iron (III) produced with 2.5 g (0.009746 moles) of S8
3moles S8 / 8 moles Fe2S3 = 0.009746 moles S8 / x
=> x = 0.009746 * 8 / 3 moles Fe2S3 = 0.026 moles Fe2S3
6) Convert 0.026 moles Fe2S3 into grams
mass in grams = number of moles * molar mass
molar mass of Fe2S3 = 207.9 g/mol
mass = 0.026 mol * 207.9 g/mol = 5.40 g
7) Answer: option D)
Answer:
See explanation
Explanation:
Many organic compounds have low melting points. This is due to the fact that many of these compounds are non polar.
However, compound X is slightly polar but still has a melting point which is far less than that of sand composed of a high melting point inorganic material.
Since sand has a much higher melting point compared to compound X, the researcher need not be worried that sand was spilled into his beaker.
From the stoichiometry of the balanced reaction equation, the correct statement are;
- For every 1 molecule of methane CH4 that reacts, 2 molecules of H2O are produced.
- For every 20 grams of methane (CH4) that reacts, 40 grams of H2O are produced.
- For every 200 moles of methane (CH4) that reacts, 400 moles of H2O are produced.
<h3>What is combustion?</h3>
The term combustion refers to the burning of fossil fuels for the purpose of energy production. The equation for reaction is CH4 + 2O2 ---> CO2 + 2H2O.
Using this equation as shown, the true statements are;
- For every 1 molecule of methane CH4 that reacts, 2 molecules of H2O are produced.
- For every 20 grams of methane (CH4) that reacts, 40 grams of H2O are produced.
- For every 200 moles of methane (CH4) that reacts, 400 moles of H2O are produced.
Learn more about combustion: brainly.com/question/15117038
Answer:
(a) See below
(b) 103.935 °F; 102.235 °F
Explanation:
The equation relating the temperature to time is

1. Calculate the thermometer readings after 0.5 min and 1 min
(a) After 0.5 min

(b) After 1 min

2. Calculate the thermometer reading after 2.0 min
T₀ =106.321 °F
ΔT = 100 - 106.321 °F = -6.321 °F
t = t - 1, because the cooling starts 1 min late

3. Plot the temperature readings as a function of time.
The graphs are shown below.