Chemistry
Fill in the blanks:
(a) Dalton used symbol …………… for oxygen and …………… for hydrogen.
(b) Symbol represents …………… atom of an element.
(c) Symbolic expression for a molecule is called …………… .
(d) Sodium chloride has two radicals. Sodium is a …………… radical while chloride is a …………… radical.
(e) Valency of phosphorus in PCl3 is …………… and in PCl5 is …………… .
(f) Valency of Iron in FeCl2 is …………… and in FeCl3 it is …………… .
(g) Formula of iron (III) carbonate is …………… .
Related Questions
Copper shows variable valency and forms two different compounds with oxygen — Cu2O and CuO.
P — A is cuprous oxide, B is cupric oxide.
Q — A is cupric oxide, B is cuprous oxide.
R — A is copper (I) oxide, B is copper (II) oxide.
Only P
Only Q
Only R
Both P and R
The figure given below shows the molecule of an element, where 'a' denotes the atom with atomic mass 32.
P — Element is tetratomic with molecular mass 128.
Q — Element is octatomic with molecular mass 256.
R — Element is crown-shaped with molecular mass 256.
Only P
Only Q
Only R
Both P and R
Name the following compounds and state how many atoms of each kind are present in one molecule of these compounds.
(a) H2SO4
(b) HClO4
(c) K2Cr2O7
(d) KMnO4
(e) K4[Fe(CN)6]
(f) Na2CrO4
(g) Mn3(BO4)2
(h) HNO2
Correct the following statements.
(a) A molecular formula represents an element.
(b) Molecular formula of water is H2O2.
(c) A molecule of sulphur is monoatomic.
(d) CO and Co both represent cobalt.
(e) Formula of iron (III) oxide is FeO.