Answer:
38.541 × 10¹⁹ formula units
Explanation:
Given data:
Mass of chromium sulfate = 0.25 g
Formula units in 0.25 g = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ formula units of water
Number of moles of chromium sulfate = Mass / molar mass
Number of moles of chromium sulfate = 0.25 g/ 392.16 g/ mol
Number of moles of chromium sulfate = 6.4 × 10⁻⁴ moles
Number of formula units:
1 mole = 6.022 × 10²³ formula units
6.4 × 10⁻⁴ moles × 6.022 × 10²³ formula units / 1 mol
38.541 × 10¹⁹ formula units
For the first blank, that is the endoplasmic reticulum
For the second, it is lysosome
For the third blank, it is the cell membrane
For the fourth, sorry I don’t know this one
For the fifth, that is the vacuole
For the sixth, that is mitochondrion
For the seventh, that is Golgi body
And lastly the eighth, it is the nucleus
Sorry I did not know what the fourth was but everything else is good.
Answer:
-5.51 kJ/mol
Explanation:
Step 1: Calculate the heat required to heat the water.
We use the following expression.
where,
- c: specific heat capacity
- m: mass
- ΔT: change in the temperature
The average density of water is 1 g/mL, so 75.0 mL ≅ 75.0 g.
Step 2: Calculate the heat released by the methane
According to the law of conservation of energy, the sum of the heat released by the combustion of methane (Qc) and the heat absorbed by the water (Qw) is zero
Qc + Qw = 0
Qc = -Qw = -22.0 kJ
Step 3: Calculate the molar heat of combustion of methane.
The molar mass of methane is 16.04 g/mol. We use this data to find the molar heat of combustion of methane, considering that 22.0 kJ are released by the combustion of 64.00 g of methane.
Hydrogen gas(H2) has a molar mass of 2 g. Molar mass of a substance is defined as the mass of 1 mole of that substance. And by 1 mole it is meant a collection of 6.022*10^23 particles of that substance.
So number of moles of H2 are 0.5 in this case. And thus it means there are (6.022*10^23)*0.5 particles( here they are molecules) in 1g of H2.
