Its b) reactant and the chemical energy of the
Answer: The approximate pressure of the gas after it is heated to 278 K is 0.468 atm.
Explanation:
Given: 
= 178 K, 
= 0.3 atm
= 278 K, 
= ?
According to Gay Lussac law, at constant volume the pressure of a gas is directly proportional to the temperature.
Formula used to calculate the pressure is as follows.
Substitute the values into above formula is as follows.
Thus, we can conclude that the approximate pressure of the gas after it is heated to 278 K is 0.468 atm.
The untrue statement is that they high melting points.
The covalent compounds are the compounds exhibiting strong intra-molecular bonds. This is due to the tightness of the atoms within the covalent molecules. The force of attraction between the individual molecules in a covalent compound seems to be weak. The covalent compounds exhibit weak intermolecular forces that hold the atoms together due to this they have a low melting point.
Cations from smallest to largest
Li⁺ ,Na⁺, K⁺ (from Periodic Table, the bigger number of period, the bigger size, of atom, so the bigger size of cation)
1) LiF smaller cation then KF
1,036 <span>853
</span><span>The lattice energy increases as cations get smaller, as shown by LiF and KF.
</span><span>I think this one should be correct answer, because the compared substances have also the same anion, and we can compare cations in them.
2) The same cation Li , so wrong statement.
3)</span>The same cation Na , so wrong statement.
4) NaCl smaller cation then KF
786 853
