6. Determine the Percentage composition of all the elements in: MgCr,O,

Silver is often extracted from ores such as K[Ag(CN)2] and then recovered by the reaction 2K[Ag(CN)2](aq)+Zn(s)2Ag(s)+Zn(CN)2(aq)+2KCN(aq) (a) How many molecules of Zn(CN)2 are produced by the reaction of 35.27 g of K[Ag(CN)2]? (b) What mass of Zn(CN)2 is produced?

When 9.59 g of a certain vanadium oxide is heated in the presence of hydrogen, and a new oxide of vanadium are formed. This new vanadium oxide has a mass of 8.76 g. When the second vanadium oxide undergoes additional heating in the presence Of hydrogen, 5.38 g of vanadium metal forms, a. Determine the empirical formulas for the two vanadium oxides. b. Write balanced equations for the Steps of the reaction. c. Determine the mass of hydrogen needed to complete the steps of this reaction.

Considering your answer to Exercise 79, which type of formula, empirical or molecular, can be obtained from elemental analysis that gives percent composition?

Is there a difference between a homogeneous mixture of hydrogen and oxygen in a 2:1 mole ratio and a sample of water vapor? Explain.

Solid calcium carbide (CaC2)reacts with liquid water to produce acetylene gas (C2H2)and aqueous calcium hydroxide. l type='a'> Write the balanced equation for the reaction that is (occurring. including all phases. If a 100.0-g sample of calcium carbide (CaC2)is initially reacted with 50.0 g of water, which reactant is limiting? Prove that mass is conserved for the reactant amounts used in pan b.

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1. An ore is analyzed for the manganese content by converting the manganese to MnsO4 and weighing it. If a 52-g sample vields MnsOa weighing 0.126 g, what would be (a) the percent Mn2Os in the sample: (b) The percent Mn?

1. Given: • 274.82 g Pb ● • 42.52 g S • 63.66 g O Wanted: percent composition by mass? % Pb % S % O

1. What is the mass percentage composition of capsaicin? 2. What is the percentage composition of sodium in baking soda, a component of some anti-acid tablets sold over the world?