Câu 3: Lập PTHH và cho biết tỉ lệ số nguyên tử, số phân tử của các chất trong mỗi phản ứng: a) SO3 + H2O - - -> H2SO4 b) CO2 + H2O - - -> H2CO3 c) HCl + NaOH - - -> NaCl + H2O d) MgO + HNO3 - - -> Mg(NO3)2 + H2O e) Al + CuO - - -> Al2O3 + C

Choose the best answer.

I think you should buy _____  pack of mineral water instead. And you can also buy _____  snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ______  cookies and soft candies.

Choose the best answer.

We should decorate our living room with _____ orange banner. We also need ________  ribbons, balloons, party hats and costume.

Choose the best answer.

I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.