Answer:
1.014×10²³ atoms
Explanation:
Given data:
Volume of tungsten = 1.6 cm³
Density of tungsten = 19.35 g/cm³
Number of atoms of tungsten = ?
Solution:
First of all we will calculate the mass of tungsten.
density = mass/volume
by putting values,
19.35 g/cm³ = mass/1.6 cm³
Mass = 19.35 g/cm³× 1.6 cm³
Mass = 30.96 g
Number of moles of tungsten:
Number of moles = mass/molar mass
Number of moles = 30.96 g/ 183.84 g/mol
Number of moles = 0.1684 mol
1 mole contain 6.022×10²³ atoms.
0.1684 mol × 6.022×10²³ atoms / 1mol
1.014×10²³ atoms
<span> 0.25 = 25/100 =1/4= 2/8 ect could you be more specific :)</span>
We have to get the amount of CaH₂ needed to generate 48 L of H₂ gas at a pressure of 0.995 atm and a temperature of 32 °C.
The amount of CaH₂ required is 79.971 gram to generate 48 L of H₂ gas at a pressure of 0.995 atm and a temperature of 32 °C .
The number of moles of H₂ gas present in 48 litre H₂ gas at a pressure of 0.995 atm and a temperature of 32°C= = 1.90 moles [using PV=nRT equation where, n= ]
To obtain one mole H₂, one mole of CaH₂ is required. So, to get 1.90 moles of H₂ gas, 1.90 moles of CaH₂ is required.
Molecular mass of CaH₂ is 42.09 g/mol. So, amount of CaH₂ needed to generate 1.90 moles of H₂ gas is equal to (1.90 X 42.09) gm= 79.971 gm.
79.971 grams of CaH₂ are needed to generate 48.0 L of H₂ gas at a pressure of 0.995 atm and a temperature of 32 °C.
Answer: gas to liquid, which cools the surrounding air.
Explanation: Condensation is the phase change of a gas into liquid state. Condensation involves a decrease in energy since temperature decreases and the kinetic energy of molecules slows down and comes close together then condenses.