Because their molecules are more tightly packed. Massdensity = ---------- Volume
So more densely packed molecules means more mass per unit volume. Hence metals are denser than non-metals.
88g ( so sorry if this isn’t correct )
Answer:
0.85 Molar Na2O
Explanation:
Determine the moles of sodium oxide, Na2O, in 10 grams by dividing by the molar mass of Na2O (61.98 g/mole).
(10 g Na2O)/(61.98 g/mole) = 0.161 moles Na2O.
Molar is a measure of concentration. It is defined as moles/liter. A 1 M solution contains 1 mole of solute per liter of solvent. [200 ml water = 0.2 Liters water.]
In this case, we have 0.161 moles Na2O in 0.200 L of solvent.
(0.161 moles Na2O)/(0.200 L) = 0.85 Molar Na2O
Resistance of a material being scratched in known as: Hardness
Answer: There are now 2.07 moles of gas in the flask.
Explanation:
P= Pressure of the gas = 697 mmHg = 0.92 atm (760 mmHg= 1 atm)
V= Volume of gas = volume of container = ?
n = number of moles = 1.9
T = Temperature of the gas = 21°C=(21+273)K= 294 K (0°C = 273 K)
R= Value of gas constant = 0.0821 Latm\K mol
When more gas is added to the flask. The new pressure is 775 mm Hg and the temperature is now 26 °C, but the volume remains same.Thus again using ideal gas equation to find number of moles.
P= Pressure of the gas = 775 mmHg = 1.02 atm (760 mmHg= 1 atm)
V= Volume of gas = volume of container = 49.8 L
n = number of moles = ?
T = Temperature of the gas = 26°C=(26+273)K= 299 K (0°C = 273 K)
R= Value of gas constant = 0.0821 Latm\K mol
Thus the now the container contains 2.07 moles.