The purity of gold is measured in karats, with pure gold being 24 karats. other purities of gold are expressed as proportional parts of pure gold. thus 18-karat gold is startfraction 18 over 24 endfraction 18 24, or 75% pure gold; 12-karat gold is startfraction 12 over 24 endfraction 12 24, or 50% pure gold; and so on. how much 2020-karat gold should be mixed with pure gold to obtain 8080 grams of 2222-karat gold? how much 2020-karat gold should be used?

Benzonitrile (c6h5cn) is reduced to two different products depending on the reducing agent used. treatment with lithium aluminum hydride followed by water forms k, which has a molecular ion in its mass spectrum at 107 and the following ir absorptions: 3373, 3290, 3062, 2920, and 1600 cm-1. treatment with a milder reducing agent forms l, which has a molecular ion in its mass spectrum at 106 and the following ir absorptions: 3086, 2850, 2820, 2736, 1703, and 1600 cm-1. l shows fragments in its mass spectrum at m/z = 105 and 77. propose structures for k and l and choose an explanation for how this could be concluded.