Water is said to be 'hard' if it
...Water is said to be 'hard' if it
easily forms ice
has to be warmed before sodium chloride dissolves in it
froms an insoluble scum with soap
contains nitrates
contains sodium ions
Correct answer is C
No explanation has been provided for this answer.
What weight of NaCl is needed to make 2.0 dm3 of a 1.5M solution? [Na = 23, Cl = 35.5]...
Which of the following compounds will leave a metal residue when heated? ...
Steam changes the colour of anhydrous cobalt (ll) chloride from ...
Which of the following molecules has two other positional isomers? ...