Ncert -Class 11- Chemistry- Some Basic Concepts of Chemistry Welcome to your Ncert -Class 11- Chemistry- Some Basic Concepts of Chemistry 1. According to Avogadro's law at the same temperature and pressure: Matter consists of indivisible atoms. Matter can neither be created nor destroyed. Equal volumes of gases contain equal number of molecules. Compounds are formed when atoms of different elements combine in a fixed ratio. None 2. A sample of diesel has the same knocking characteristics as a 60 ml mixture of cetane and 𝑎 -methyl naphthalene mixed in 2 :1 ratio .The cetane number of the diesel sample is : 33.3 60 66.6 40 None 3. According to Avogadro's law the correct statement area) Volume of gas is directly proportional to the no. of moles at constant T and P.b) The pressure of gas is directly proportional to temp. of the gas under all conditions.c) Equal volumes of different gases under similar conditions consist of equal no. of molecules.d) Equal volumes of different gas under same conditions have equal no. of atoms. c,d a,c b,c d,b None 4. Samples of gases \( O_2, N_2, CO, \) and \( CO_2 \) under the same conditions of temperature and pressure contain the same number of molecules represented by \( X \). The molecules of oxygen occupy \( V \) litres and have a mass of \( 8 \, \text{g} \). Under the same conditions of temperature and pressure, what is the volume occupied by molecules of \( N_2 \)? V/2 2V 4V V None 5. 60g of solution containing 40% by mass of NaCl are mixed with 100g of a solution containing 15% by mass NaCl. Determine the mass percent of sodium chloride in the final solution. 24.4% 78% 48.8% 19.68% None 6. What weight of \( \text{NaHSO}_3 \) is required to react with \( 100 \, \text{mL} \) of solution containing \( 0.33 \, \text{g} \) of \( \text{NaIO}_3 \) according to the following reaction: \[ \text{IO}_3 ^{-}+ \text{HSO}_3^{-} \rightarrow I ^{-} + \text{SO}_4^{2-}\] 5.2g 0.52g 1.04g 10.4g None 7. 0.1 g of a solution containing \( \text{Na}_2\text{CO}_3 \) and \( \text{NaHCO}_3 \) requires 10 mL of 0.01 N HCl for neutralization using phenolphthalein as an indicator. Wt % of \( \text{Na}_2\text{CO}_3 \) in the mixture is 25 50 30 10.6 None 8. A mixture of \( \text{SO}_2 \) and \( \text{O}_2 \) was made to react in such a way that every gram of mixture gives maximum amount of \( \text{SO}_3 \). The mass % of \( \text{SO}_2 \) in the mixture is 80% 60% 30% None of these None 9. A compound has an empirical formula of C2HBr. If the molar mass of the compound is 314.7 g/mol, what is the molecular formula of the compound? (Atomic mass of Br = 80g/mol) $$ C_{4}H_{2}Br_{2}$$ $$ C_{8}H_{4}Br_{4}$$ $$C_{2}HBr$$ $$ C_{6}H_{3}Br_{3}$$ None 10. If a solution contains 34.2 g of sugar in 100 g of water. Find the concentration inn terms of mass by mass percentage of the solution? 20 % 25.48 % 10 % 50 % None 11. Vapour density of a gas is 22. Its molecular mass will be: 22g 33g 44g 11g None 12. In a compound A containing carbon, hydrogen and oxygen, the % of hydrogen is one sixth that of carbon which is 1.5 times of oxygen. What is the simplest formula for the compound:- $$\text{C}_2\text{H}_6\text{O}$$ $$\text{C}_2\text{H}_4\text{O}_2$$ $$\text{C}_2\text{H}_4\text{O}$$ $$\text{C}\text{H}_6\text{O}$$ None 13. According to Gay Lussac’s Law of Gaseous Volumes, when gases combine or are produced in a chemical reaction they do so in a ______ ratio by volumes provided all gases are at same temperature and pressure. simple inverse uncertain equal None 14. What percent of a sample of nitrogen must be allowed to escape if its temperature, pressure, and volume are to be changed from 220ºC, 3atm and 1.65 litre to 110ºC, 0.7 atm and 1.00 litre respectively? 86.8% 71.8% 76.8% 81.8% None 15. A substance contains 3.4%𝑆. if it contain two atom of sulphur per molecule then minimum molecular weight of substance will be: 1882 94.1 282.3 188.2 None 16. According to Avogadro Law equal volumes ofall gases at the same temperature and pressure should contain ---------- number of molecules . different similar unequal equal None 17. 3g of activated charcoal was added to 50mL of acetic acid solution (0.06N) in a flask. After an hour it was filtered and the strength of the filtrate was found to be 0.042N. The amount of acetic acid absorbed (per gram of charcoal) is ? 54mg 36mg 42mg 18mg None 18. A mixture of ethane and neon having a volume of 20ml requires 49 ml of oxygen for complete combustion. The percentage of ethane in the mixture is: 35 % 64 % 70 % 30 % None 19. Two oxide of metal contain 27.6% and 30% oxygen respectively. If the formula of first oxide is \(M_{3}O_{4}\) then formula of second oxide is - $$MO_{2}$$ $$MO$$ $$M_{2} O_{3}$$ $$M_{2} O$$ None 20. The law which suggests 𝑛1=𝑛2 for two solutions at same temperature and pressure is van't Hoff Boyle's law Henry's law van't Haff - avogadro's law van't Hoff's law None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
