Answer:
B. People live longer than they used to
Explanation:
None of the other answers are correct.
Molar mass of Na2SO4*10H2O is 322.1949 g/mol
Explanation:
Given parameters:
Number of molecules = 4.21 x 10²³ molecules
Unknown parameters:
Number of moles
Solution:
A mole can be defined as the amount of a substance that contains the avogadro's number of particles i.e 6.02 x 10²³
To find the number of moles:
Number of moles =
}[/tex]
Number of moles =
}{
}[/tex]
Number of moles of CaCl₂ = 0.699moles
Learn more;
mole calculation brainly.com/question/13064292
#learnwithBrainly
This question requires the knowledge of density.
The density of ethyl alcohol = 789 kg m⁻³
The density of water = 1000 kg m⁻³
Density = Mass / Volume
By applying ethyl alcohol,
789 kg m⁻³ = Mass / 0.9 m³
Mass = 710.1 kg
hence the mass of 0.9 m³ ethyl alcohol is 710.1 kg.
Then by applying water,
1000 kg m⁻³ = 710.1 kg / Volume
Volume = 0.7101 m³
= 0.7 m³
hence the equal water volume is 0.7 m³