Answer:
A change in quantity demanded is as a result of a change in price. It leads only to movement along the demand curve. If price increases, quantity demanded falls and if price falls, quantity demanded rises.
A change in demand for icecream in caused by other factors other than the price of Ice cream. Some of these factors include:
1. Taste 
2. Weather 
3. Change in price of substitutes 
4. Expectations 
A change in demand leads to the demand curve either shifting to the left or to the right. 
Step-by-step explanation: