Help please I dont know

Which of the following pairs of elements belong to the same groupa. h and he b. li and bec. c and pb d. ga and ge

The molar mass of iron(fe) is 55.8 g/mol. what is the mass in grams of 2.25 moles of iron?

Find the enthalpy of neutralization of hcl and naoh. 87 cm3 of 1.6 mol dm-3 hydrochloric acid was neutralized by 87 cm3 of 1.6 mol dm-3 naoh. the temperature rose from 298 k to 317.4 k. the specific heat capacity is the same as water, 4.18 j/k g. a. -101.37 kj b. 7055 kj c. 10,1365 kj