Chemistry
Identify the substance underlined in each of the following:
(i) The electrode that increases in mass during the electro-refining of silver.
(ii) The acid that is a dehydrating as well as a drying agent.
(iii) The catalyst used to oxidize ammonia into nitric oxide.
Related Questions
(i) State the volume occupied by 40 gm. of methane at stp if it's vapour density is 8.
(ii) Calculate the number of moles present in 160 g of NaOH.
[Na = 23, H = 1, O = 16]
Identify the salts P, Q, R from the following observations:
(i) Salt P has light bluish green colour. On heating, it produces a black coloured residue. Salt P produces brisk effervescence with dil. HCl and the gas evolved turns lime water milky, but no action with acidified potassium dichromate solution.
(ii) Salt Q is white in colour. On strong heating, it produces buff yellow residue and liberates reddish brown gas. Solution of salt Q produces chalky white insoluble ppt. with excess of ammonium hydroxide.
(iii) Salt R is black in colour. On reacting with conc. HCl, it liberates a pungent greenish yellow gas which turns moist starch iodide paper blue black.
Copy and complete the following paragraph using the options given in brackets:
Alkenes are a homologous series of (i) …………… [saturated/unsaturated] hydrocarbons characterized by the general formula (ii) …………… [CnH2n+2/CnH2n]. Alkenes undergo (iii) …………… [addition/substitution] reactions and also undergo (iv) …………… [hydrogentaion/dehydrogenation] to form alkanes.
Write balanced chemical equations, for the preparation of given salts (i) to (iii) by using the methods A to C respectively.
A: Neutralization
B: Precipitation
C: Titration(i) Copper sulphate
(ii) Zinc carbonate
(iii) Ammonium sulphate