B. The sand increases friction by increasing roughness.
The Lewis Structure of HCN is shown below,
Number of Bonding Electrons: In HCN Hydrogen is bonded to Carbon through single bond and Nitrogen is bonded to Carbon through Triple Bond. Single bond is formed by two bonding electrons, while, triple bond is formed by six bonding electrons, Hence,
Number of Bonding Electrons = 8
Number of Non-Bonding Electrons:
In HCN there is only one lone pair of electron present on Nitrogen atom which is not taking part in bonding. Hence,
Number of Non-Bonding Electrons = 2
Result: Number of Bonding Electrons = 8 Number of Non-Bonding Electrons = 2
I got 134.91 but if you round it you’ll get 135
Answer: 26.5 mm Hg
Explanation:
The vapor pressure is determined by Clausius Clapeyron equation:
where,
= initial pressure at = ?
= final pressure at = 100 mm Hg
= enthalpy of vaporisation = 28.0 kJ/mol =28000 J/mol
R = gas constant = 8.314 J/mole.K
= initial temperature =
= final temperature =
Now put all the given values in this formula, we get
Thus the vapor pressure of in mmHg at 26.5 ∘C is 26.5
Ionic crystals are hard because of tight packing lattices, say, the positive and negative ions are strongly attached among themselves.