The acid which contains four hydrogen atoms — (a) Formic acid (b) Sulphuric acid (c) Nitric acid (d) Acetic acid
Acetic acid (CH3COOH) contains four hydrogen atoms.
What is the term defined : i) A base which is soluble in water.
Alkali is a base which is soluble in water.
A health food store has a large display of bracelets made of copper metal. The storekeeper claims that the copper atoms from the bracelet diffuse into the body and the wearer is protected against rheumatoid diseases. Kuber wants to buy a bracelet for his grandmother who is suffering from arthritis. But his friend Ramesh suggests him against it. He says that it is a superstitious belief and wearing any metal on the body does not cure someone of the disease. Answer the following questions based on the above information: (𝒊) Do you think that Kuber should agree to Ramesh’s advice and not buy the bracelet? Give one reason. (𝒊𝒊) What values are displayed by Ramesh through his suggestion? (𝒊𝒊𝒊) Suggest one activity to promote these values.
(i) Yes. Because it is a superstition and not a scientifically proven fact. (ii) Awareness, scientific attitude, helpfulness. (iii) Group discussion on value clarification/Role play.
Calculate the number of electrons present in 15.4 of carbon tetrachloride CCl4
Number of moles of CCl4 = = ∵ = 0.1 mole 1 mole of CCl4 = 6.022 × 1023 molecules of CCl4 ∴ 0.1 mole of CCl4= 0.1 × 6.022 ×…
You are provided with a fine white coloured powder which is either sugar or salt. How would you identify it without tasting?
On heating the power, it will char if it is a sugar. Alternatively, the powder may be dissolved in water and checked for its conduction of electricity. If it conducts,…
What is the fraction of the mass of water due to neutrons?
Mass of one mole (Avogadro Number) of neutrons ~ 1 g Mass of the one neutrons =(1 / 𝐴𝑣𝑜𝑔𝑎𝑑𝑟𝑜 𝑁𝑢𝑚𝑏𝑒𝑟 (𝑁𝐴)) g Mass of 8 molecule of water = 𝑀𝑜𝑙𝑎𝑟 𝑚𝑎𝑠𝑠…
A big drop has volume 1.0 mL. How many molecules of water are there is this drop, If the density of water is 1g/mL?
Volume of drop of water = 1.0 mL Density of water = 1.0 g/mL ∴ Mass of drop of water = Volume × Diabesity = 1.0 g Molecular mass of…
A colorless liquid is thought to be a pure compound. Analysis of three samples of the material yield the following results.
| Mass of Sample | Mass of carbon | Mass of Hydrogen | |
| Sample 1 | 1.0 g | 0.862 g | 0.138 g |
| Sample 2 | 1.549 g | 1.335 g | 0.214 g |
| Sample 3 | 0.988 g | 0.852 g | 0.136 g |
Analysis Mass of Carbon + Mass of Hydrogen = Mass of Sample Sample 1 0.862 g + 0.138 g = 1.0 g Sample 2 1.335 g + 2.214 g =…
Calculate the ratio between the mass of one atom of hydrogen and mass of one atom of silver.
1 mole of H atoms = 1 g 1 mole of H atoms = 6.022 × 1023 atoms. Mass of 6.022 x 1023 atoms of H = 1g ∴ Mass…
In photosynthesis, 6 molecules of carbon dioxide combine with an equal number of water molecules through a complex series of reactions to give a molecule of glucose having a molecular formula C6H12O6. How many grams of water would be required to produce 18 g of glucose? Compute the volume of water so consumed assuming the density of water to be 1g cm-3.
6CO2 + 6 H2O →Chlorophyll + Sunlight → C6H12O6 + 6O2 1 mole of glucose needs 6 moles of water 180 g of glucose needs (6 × 1 8) g…