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PLEASE HELP ME!

When magnesium powder is heated, it combines with oxygen to form white magnesium oxide powder.

(a) State one use of magnesium oxide.

(b) Write the chemical equation of this reaction.

(c) Calculate the mass of magnesium oxide formed if 3g magnesium is completely burnt in excess oxygen.

(d) The magnesium oxide is basic and reacts with hydrochloric acid to form magnesium chloride salt and water. Write the chemical equation of this reaction. (Relative atomic mass of O=16,Mg=24) ​

1 Answer

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Step-by-step explanation:

a. Magnesium oxide is used mainly in soil treatment and groundwater remediation, wastewater treatment, etc. it is used for it's acid buffering capacity and effectiveness in dissolving heavy metals.

b. MgO is the chemical equation for the reaction.

c. multiply the given mass of O2 by the inverse of it's molar mass. multiply the molar ratio (from the balanced equation) between O2 and MgO. Multiply by the molar mass of MgO. 32g O2 x 1 mol O2 ... 32g O2 x 2mol MgO 1mol O2 x 40g MgO. .... 1mol MgO = 80 g.

d. Mg (s) + 2 HCl (aq) produces MgCl 2(aq) + H 2 (g). Where the letter "s" stands for solids, and "g" is for gas and "aq" represents aqueous solution.

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