Answer is: 0,327 g/l.
<span>Ideal gas law: pV = nRT.
</span><span>V - volume, the amount of space occupied by the gas.
</span><span>p - pressure ,1 atm = 760 torr = 760 mmHg.
</span><span>n - amount of substance.
</span>T - temperature, 273 K = 0°<span>C. T = 25 + 273 = 298K.
</span>R - ideal gas constant,<span> R = 0,08206 L</span>·atm/mol·K<span>.
</span>d(He) = M·p ÷ R·T.
d - density.
M - molar mass.
d(He) = 4g/mol · 2atm ÷ 298K · 0,08206 L·atm/mol·K = 0,327 g/l.
Oxygen is the 2nd most electronegative element. When you examine a periodic table, you will find that (excluding the noble gases) the electronegativity values tend to increase as you go to the right and up. The reverse statement is that the values tend to decrease going down and to the left.
Metals don't form covalent bonds because of the low ionization energes of the metal atoms. It is easier for them to release electrons rather than sharing it. But this is not always the case, there are some metals that can form covalent bonds.
Answer:
it may also become impure,I think.
Explanation:
The reaction is CaCO
3
+2HCl→CaCl
2
+H
2
O+CO
2
.
Thus, 2 moles of HCl reacts with one mole of calcium carbonate to produce one mole each of calcium chloride, water and carbon dioxide respectively.
Hence, 3 moles of HCl will react with excess of calcium carbonate to produce 3×
2
1
=1.5 mol of carbon dioxide
