Answer:
A solution is made by dissolving 4.87 g of potassium nitrate in water to a final volume of 86.4 mL solution. The weight/weight % or percent by mass of the solute is :
<u>2.67%</u>
Explanation:
Note : Look at the density of potassium nitrate in water if given in the question.
<u><em>You are calculating </em></u><u><em>weight /Volume</em></u><u><em> not weight/weight % or percent by mass of the solute</em></u>
Here the <u>weight/weight % or percent by mass</u> of the solute is asked : So first convert the<u> VOLUME OF SOLUTION into MASS</u>
Density of potassium nitrate in water KNO3 = 2.11 g/mL
Density = 2.11 g/mL
Volume of solution = 86.4 mL
Mass of Solute = 4.87 g
Mass of Solution = 183.2 g
w/w% of the solute =
w/w%=2.67%
Answer:
ΔH°f(C₈H₁₈(g)) = -210.9 kJ/mol
Explanation:
Let's consider the combustion of C₈H₁₈.
C₈H₁₈(g) + 25/2 O₂(g) ⟶ 8 CO₂(g) + 9 H₂O(g) ΔH°rxn = − 5113.3 kJ
We can calculate the standard enthalpy of formation of C₈H₁₈(g) using the following expression.
ΔH°rxn = 8 mol × ΔH°f(CO₂(g)) + 9 mol × ΔH°f(H₂O(g)) - 1 mol × ΔH°f(C₈H₁₈(g)) - 25/2 mol × ΔH°f(O₂(g))
1 mol × ΔH°f(C₈H₁₈(g)) = 8 mol × ΔH°f(CO₂(g)) + 9 mol × ΔH°f(H₂O(g)) - 25/2 mol × ΔH°f(O₂(g)) - ΔH°rxn
1 mol × ΔH°f(C₈H₁₈(g)) = 8 mol × (-393.5 kJ/mol) + 9 mol × (-241.8 kJ/mol) - 25/2 mol × 0 kJ/mol - (− 5113.3 kJ)
ΔH°f(C₈H₁₈(g)) = -210.9 kJ/mol
<u>Answer:</u> The percent composition of in taconite is 37.6 %.
<u>Explanation:</u>
We are given:
Mass of taconite pellets = 1 ton = 907185 g (Conversion factor: 1 ton = 907185 g)
Mass of iron produced = 545 lb = 247212 g (Conversion factor: 1 lb = 453.6 g )
We know that:
Molar mass of iron = 55.85 g/mol
Molar mass of = 231.53 g/mol
1 mole of contains 3 moles of iron atom and 4 moles of oxygen atom
(3 × 55.85) = 167.55 g of iron is produced from 231.53 grams of
So, 247212 grams of iron will be produced from = of
To calculate the percentage of in taconite, we use the equation:
Mass of taconite = 907185 g
Mass of = 341611.43 g
Putting values in above equation, we get:
Hence, the percent composition of in taconite is 37.6 %.
Liquefied Natural Gas
Explanation:
Gases are usually liquefied in the downstream sector during crude processing. These natural gases are products of distillation of crude oil in fractionating columns. Some of them are also found in geological formations.
- To easily transport these gases, they are liquefied in vessels that carries them from one place to another.
- Liquefaction is the process of converting a gas or solid into a liquid form.
- Gases are usually compressed under very high pressure into vessels through which can make them easier to transport.
- Gases do not have a fixed volume and they typically assume the volume of any container they are taken into.
Learn more:
Natural gas brainly.com/question/4344417
#learnwithBrainly
Answer:
Final temperature = 22.21 °C
Explanation:
Heat gain by ethanol = Heat lost by water
Thus,
Where, negative sign signifies heat loss
Or,
<u>For ethanol:
</u>
Density = 0.789 g/mL
Volume = 55.0 mL
Considering the expression for density as:
So,
So, Mass= Density*Volume = 0.789 g/mL * 55.0 mL = 43.395 g
Initial temperature = 9.0 °C
Specific heat of ethanol = 2.57 J/g°C
<u>For water:
</u>
Density = 1.0 g/mL
Volume = 55.0 mL
Considering the expression for density as:
So,
So, Mass= Density*Volume = 1.0 g/mL * 55.0 mL = 55.0 g
Initial temperature = 28.6 °C
Specific heat of water = 0.450 J/g°C
So,
<u>Final temperature = 22.21 °C </u>