Pure water is called distilled water or deionized water.
1) Solids have a fixed shape
The particles of solids are held into their positions and are only able to vibrate about fixed points. The strength of the bonding means that the particles have their own shape, which they retain, and do not take the form of the container they are in.
2) Solids may not flow
The molecules of liquids are able to slide past one another due to weaker bonds between particles. This allows the liquid to flow; whereas, this movement is not possible in solids so they cannot flow.
3) Solids may fracture
The fact that solids possess a rigid structure means that they have the ability to fracture. Although some are able to withstand more stress than others, all solids may break. This breakage occurs when the intermolecular bonds are mechanically broken. This is not possible in the case of liquids because such rigid intermolecular bonds do not exist.
Answer:
Explanation:
Polyatomic ions are ions (usually anions) that are made up of more than one atom. In order to determine the charge of anions, one can first identify the charge of the metal (which forms the cation) in a compound (which is usually easy to know) before predicting the charge of the anion. The charges are usually exchanged to form denominator of the other reacting atom/molecule, but if divisible, they are divided first before the exchange.
(a) The polyatomic ion in KNO₂ is NO₂ with the ionic equation below showing it's charge
KNO₂ ⇒ K⁺ + NO₂⁻
From the above, we can deduce that the charge of NO₂ is "1-"
(b) The polyatomic ion in CaSO₄ is SO₄ with the ionic equation below showing it's charge
CaSO₄ ⇒ Ca²⁺ + SO₄²⁻
The charge of SO₄ from the above equation is "2-"
(c) The polyatomic ion in Mg(NO₃)₂ is NO₃ with the ionic equation below showing it's charge
Mg(NO₃)₂ ⇒ Mg²⁺ + NO₃⁻
From the above equation, it can be deduced that the charge of NO₃ is "1-"