1. Identify the molecule produced when electrical discharges pass through the oxygen in air
Explanation: O3 is a strong oxidizing agnent and it can be generated by passing electric current through oxygen in the air.
2. What are the units of KC for
Explanation: As number of moles of reactants and product are same. So, there will be no units for Kc. e.g.,
3. What will happen if [OH-] increases?
Explanation: When [H+] and [OH-] are equal, solution will be neutral. If [OH-] increases then [H+] decreaes and solution becomes more basic.
4. Which of the following is a Lewis acid
Explanation: OH-, NH3 and F- have electron pairs, so they can donate electron pair and hence act as lewis bases. Howevr, BF3 has electron deficient B atom, which can accept electron pair, hence acts as lewis acid. Therefore, correct option is d).
5. Which of the following is an aldehyde?
Explanation: In aldehydes, carbonyl carbon must have at least one hydrogen directly bonded to it. Carbonyl group (CO) is present in options b), c) and d). Among these, carbonyl carbon is bonded directly with hydrogen only in option c). So c) is the correct answer.
6. Fehlings solution is used to determine the presence of:
Explanation: Fehlings solution is used to determine the presence of aldehyde and ketone. For aldehydes, Fehling solution give positve test while for ketones, it give negative test.
7. Raffinose produces units of simple sugars when hydrolysed
Explanation: Raffinoe C18H35O16 is made up of three monosaccharide (simple sugar) units known as glucose.fructose and glactose.
8. The substances which fight against diseases in living organisms are
Explanation: Among these classes of compounds, proteins regulate the production of antibodies which fight against the disease.
9. Each DNA nucleotide consists of.
Explanation: Each DNA nucleotide is made up of three componants which are deoxyribose sugar, a phosphate group and a nitrogeneous base. Nitrogeneous base are of further four types such as adenine, guanine, cytocine and thiamine
10. Permanent hardness of water can be removed by:
Explanation: Permanant hardness of water can be removed by ion exchange method, that involves usually sodium zeolite. In this method, cations causing permanant hardness such as ca and mg ions are exchanged with sodium ions.
11. The chemical formula of ammonium carbamate
Explanation: The chemical formula or ammonium carbamate is NH2COONH4 which upon steam distillation produces urea NH2CONH2 and water.
12. Which of the following process is reduction in nature?
Explanation: In smelting, metals are are extracted by reducing them. FBISE Paper (2018) MCQs and Answers with explanation
Sir why some metals are extracted by the methods you mentioned i e roasting ,smelting etc.while some are extracted by electrolytic methods exclusively??
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