Select the cations responsible for water hardness.1) ca2+ 2) co3−2 3) caco3 4) mg2+

The correct options are: 1. Ca²⁺ and 4. Mg²⁺      

Explanation:

Hard water is the water with high mineral content. Temporary hardness and permanent hardness are the two types of hardness of water.

Temporary hardness is due to the presence of dissolved bicarbonate minerals. These minerals present in the water, dissociate to give multivalent calcium cations (Ca²⁺) and magnesium cations (Mg²⁺).

Therefore, the presence of metal cations such as calcium cations (Ca²⁺) and magnesium cations (Mg²⁺) makes the water hard.

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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