7. The molar mass of pottasium dichromate(K2Cr2O7) = 294 g.
Answer:
Factories because they have helped with producing goods faster but in the meanwhile, our future will slowly get warmer.
Explanation:
<span>The option A is correct answer. The isotopes are X and Y. The isotopes are those which have same atomic number but different mass number. Since atomic number has same number of protons or electrons. Thus, isotopes have same number of protons or electrons. Therefore, X and Y are isotopes.</span>