For example, copper is used for electrical<span> wiring because it is a </span>good conductor of electricity<span>. </span>Metal<span> particles are held together by strong metallic bonds, which is why they have high melting and boiling points. The free electrons in </span>metals<span> can move through the </span>metal<span>, allowing </span>metals<span> to conduct </span>electricity<span>.</span>
Answer : 9773 kJ
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and 
for the reaction comes out to be negative.
To calculate the moles :
Given : Change in enthalpy on combustion of 1 mole of methanol = -1278 kJ
According to stoichiometry :
1 mole of methanol produce energy = 1278 kJ
Thus 7.647 moles of methanol produce energy =
Thus 9773 kJ of energy is produced from burning 245.0 g of methanol in excess oxygen
Density = mass / volume
= 69g / 23 ml
= 3 g / ml.
Thus, the density of the sample is 3 grams per ml or 3g/ ml
Answer:
False
Explanation:
In an exothermic process, the reaction gives off heat, and not takes it in. If it takes it in from the surroundings, then it would be endothermic.
Answer:
weaker and longer
Explanation:
Since there are 3 bonds in ethyne in comparision with the 2 bonds of ethyne between carbon atoms, they are attracted more to each other → the bond gets shorter . And since there are one more bond that supports the union → the bond gets stronger
thus the carbon-carbon double bond in ethene is weaker and longer than the carbon-carbon triple bond in ethyne
