Answer:
Mass = 88.12 g
Explanation:
Given data:
Mass of iron oxide = 126 g
Mass of iron formed = ?
Solution:
Chemical equation:
Fe₂O₃ + 3CO → 2Fe + 3CO₂
Number of moles of iron oxide:
Number of moles = mass/molar mass
Number of moles = 126 g/ 159.69 g/mol
Number of moles = 0.789 mol
Now we will compare the moles of iron with iron oxide.
Fe₂O₃ : Fe
1 : 2
0.789 : 2/1×0.789 = 1.578 mol
Mass of iron:
Mass = number of moles ×molar mass
Mass = 1.578 mol × 55.84 g/mol
Mass = 88.12 g
Answer:
375.2 kJ
Explanation:
- H₂(g) +F₂(g) → 2HF(g) +536kJ
The information the equation above provides lets us know that when 2 mol of hydrogen fluoride (HF) are produced, 536 kJ of energy (as heat) is produced.
We can then <u>state a rule of three</u>:
And <u>solve for X</u>:
- X = 1.4 mol * 536 kJ / 2 mol
Answer:
D) Low temperatures
Explanation:
Non-metals are elements that do not show metallic characteristics like heat conductivity, electrical conductivity, malleability, e.t.c. They are generally less dense and are bonded with weak forces in between their compounds.
The weakness of non-metals is the chief reason why they generally tend to have low boiling point. Only the presence of impurities can cause an elevation in their boiling points.
Metals on the other hand are good heat conductors and they generally have a high boiling point.
Answer:
0.4383 g
Explanation:
Molality is defined as the moles of the solute present in 1 kg of the solvent.
It is represented by 'm'.
Thus,
Given that:
Mass of solvent, water = 150 g = 0.15 kg ( 1 g = 0.001 g )
Molality = 0.050 m
So,
Molar mass of NaCl = 58.44 g/mol
Mass = Moles*Molar mass = 
= 0.4383 g
