By increasing atomic number
Answer:
D) burning a candle
A demonstration that contains both physical and chemical changes will be BURNING OF A CANDLE.
<em>This is because when a candle is lighted up, on the top of it (where we see flame) the oxygen and other gases present around will be chemically changed (burned up)</em>
<em>When the wax in the top of the candle will get melted due to the heat of the fire a physical change takes places.</em>
1 - 8
2 - 13
3 - 20
4 - 19
5 - 19
6 - 22
* protons - Atomic number
electrons - number of electrons is equal to number of protons k-41 is neutral
neutrons - Mass number - Atomic number
= 41 -19
= 22
Answer:
Anhydride, any chemical compound obtained, either in practice or in principle, by the elimination of water from another compound. Examples of inorganic anhydrides are sulfur trioxide, SO3, which is derived from sulfuric acid, and calcium oxide, CaO, derived from calcium hydroxide
Explanation:
<h3>
<em><u>examples</u></em><em><u>.</u></em></h3>
1)acid anhydride.
2)basic anhydrides.
<h3>
<em><u>reactions</u></em><em><u>. </u></em></h3>
1)reaction with water
(CH3CO)2O + H2O → 2 CH3CO2H.
Answer: d) -705.55 kJ
Explanation:
Heat of reaction is the change of enthalpy during a chemical reaction with all substances in their standard states.
Reversing the reaction, changes the sign of 
On multiplying the reaction by 
, enthalpy gets half:
Thus the enthalpy change for the given reaction is -705.55kJ
