19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
The hardness of water is estimated by
A water sample is said to contain permanent hardness if water contains
Which of the following is not a disadvantage of using hard water?
The temporary hardness of water due to calcium bicarbonate can be removed by adding
The formula for permutit or zeolite which is used as softener in ion-exchange method is
The formula of exhausted permutit is
Which of the following is a true structure of H2O2 in solid phase ? (a) (b) (c) (d)
When CO2 is bubbled through a solution of barium peroxide in water
Which of the following metals evolves hydrogen on reacting with cold dilute HNO3? (AIPMT 1989)
The ionization of hydrogen atom would give rise to (AIPMT 1990)
Hydrogen peroxide molecules are (AIPMT 1991)
At its melting point, ice is lighter than water because (AIPMT 1992)
Water gas is produced by (AIPMT 1992)
One would expect proton to have very large (AIPMT 1993)
The O – O – H bond angle in H2O2(g) is about (AIPMT 1994)
Which of the following groups of ions makes the water hard? (AIPMT 1994)
The volume strength of 1.5 N H2O2 solution is (AIPMT 1997)
Which one of the following pairs of substances on reaction will not evolve H2 gas? (AIPMT 1998)
The hardness of water is estimated by (Manipal 2004)
When CO2 is bubbled through a solution of barium peroxide in water (AFMC 2005)
How many neutrons are present in tritium nucleus? (RPMT 2006)
How many ‘mL’ of perhydrol is required to produce sufficient oxygen which can be used to completely convert 2 L of SO2 gas? (BITSAT 2007)
Hardness of water is due to the presence of salts of (AMU 2007)
The formula of Calgon, used for water softening is (EAMCET 2007)
Radioactive isotope of hydrogen is (RPMT 2007)