The potassium chloride is KCl. The gram formula mass of KCl is 39+35.5=74.5 g/mol which means 74.5 g per mole of KCl. So the mass of KCl is 6.90*74.5=514 g.
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>
Answer:
0.0286 moles
Explanation:
Given mass,
Molar mass of boron, M = 10.811 g/mol
Hence, there are 0.0286 moles in given mass of boron.
1 mole of
is 180 grams. (Molar mass).
18 is
of 180 , so it means 18 grams of
is
moles
To find a molecule's molar mass, you should multiply each atom's number with their atomic mass, in the molecule and add them I mean, there are 6 Carbon atoms, 12 Hydrogen atoms and 6 Oxygen atoms. So,
Atomic mass of Carbon is approximately, 12 amu (atomic mass unit), Hydrogen's is approximately, 1 and Oxygen's is approximately, 16. So :