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The three elements most needed in common fertilisers are:
The two metal ions that cause hardness to water are:
The uranium fuel used worldwide is mainly in the form of
The working of a dry cell is based on
There are two elements calcium (atomic number 20) and argon (atomic number 18) The mass number of both the elements is 40. They are therefore known as
Thermal electricity is generated by using which of these ?
Trichloroacetaldehyde was subject to Cannizzaros reaction by using NaOH. The mixture of the products contains sodium trichloroacetate and another compound. The other compound is
Two elements which can form a big number of compounds are
Vander Walls equation explains the behaviour of
Vinegar made by fermentation from cane sugar contains
