125 Each half life it divides by 2 the amount
1000/2=500
500/2=250
250/2=125
thermal contact
When heat flows from one object or substance to another it is in contact with, the objects or substances are said to be in thermal contact. The state where objects in thermal contact with each other reach the same temperature, no heat flows between them.
ITS HYDROGEN IONS CONCERNTATION IS MORE BECAUSE ON THE LEFT SIDE OF PH SCALE THERE IS INCREASING OF H+ IONS AND PH IS LESS THAN 7 IS MORE ACIDIC IN NATURE