Chemistry
State one observation :
(a) Concentrated nitric acid is reacted with sulphur.
(b) Lead nitrate is heated strongly in a test tube.
(c) Zinc nitrate crystals are strongly heated.
(d) Copper nitrate crystals are heated in a test tube.
Related Questions
Explain why
(a) Only all-glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.
(b) Nitric acid is kept in a reagent bottle for a long time.
(c) Iron is rendered passive with fuming HNO3. Give reason.
(d) Dil. HNO3 is generally considered a typical acid but not so in it's reaction with metals.
(e) When it is left standing in a glass bottle, concentrated nitric acid appears yellow.
A dilute acid B does not normally give hydrogen when reacted with metals but does give a gas when reacts with copper. Identify B. Write equation with copper.
Give balanced equation for the following :
(a) dilute nitric acid and copper carbonate.
(b) oxidation of carbon with conc. HNO3.
(c) Laboratory preparation of nitric acid.
(d) Action of heat on a mixture of copper and concentrated nitric acid.
X, Y and Z are three crystalline solids which are soluble in water and have a common anion.
To help you to identify X, Y and Z, you are provided with the following experimental observations. Copy and complete the corresponding inferences in (a) to (e).(a) A reddish-brown gas is obtained when X, Y and Z are separately warmed with concentrated sulphuric acid and copper turning added to the mixture.
INFERENCE 1: The common anion is the …………… ion.
(b) When X is heated, it melts and gives off only one gas which re-lights a glowing splint.
INFERENCE 2: The cation in X is either …………… or ……………
(c) The action of heat on Y produces a reddish-brown gas and a yellow residue which fuses with the glass of the test tube.
INFERENCE 3: The metal ion present in Y is the …………… ion.
(d) When Z is heated, it leaves no residue. Warming Z with sodium hydroxide solution liberates a gas which turns moist red litmus paper blue.
INFERENCE 4: Z contains the …………… cation.
(e) Write the equations for the following reactions.
- X and concentrated sulphuric acid (below 200° C). (One equation only for either of the cations given in INFERENCE 2).
- Action of heat on Y.
- Concentrated nitric acid is added to copper turnings kept in a beaker.