The last one 1) exothermic; 2) exothermic
Bonding Continuum<span>. Trends in the Periodic Table and </span>Bonding<span>. Ionic </span>Bonds. Ionic bonds<span> are formed between atoms with a large difference in electronegativities. ... The ionic </span>bond<span> is the electrostatic force of attraction between a positive and negative ion.</span>
Answer:

Explanation:
First, find the mass of empirical formula, CH. 12.01 g/mol is for carbon, and 1.008 g/mol is for hydrogen. 12.01+1.008=13.018 G/mol CH. Divide 78.110 G/mol by 13.018 g/mol. You get approximately 6. Multiply that by the subscript of each element. 6(CH)=

Answer: 0.00867 moldm-3
Explanation:
Since the reaction is 1st order,
Rate of reaction=∆[A]÷t
0.646-0.0146/72.8= 0.00867
Remember that in a first order reaction, the rate of reaction depends on change in the concentration of only one of the reaction species, A in the problem above.