Please help i got no clue how to do dis

Aluminum–lithium (al-li) alloys have been developed by the aircraft industry to reduce the weight and improve the performance of its aircraft. a commercial aircraft skin material having a density of 2.47 g/cm3 is desired. compute the concentration of li (in wt%) that is required.

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.