I believe D hopefully this helps
Answer:
having a smooth or lubricated surface may help decrease friction.
Explanation:
Answer:
This is very easy Cuz We have 2Na2O We have O2 so thats molecule of Oxygen and its same on product We need to balance Na on start We have 1 on product We have 2 so Just put 2 at start....
Explanation:
Sorry for bad english not my first language :(
2Na+O2-->2Na20
Answer : The time required for decay is, 84 days.
Explanation :
Half-life of chromium-51 = 28 days
First we have to calculate the rate constant, we use the formula :
Now we have to calculate the time required for decay.
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = time taken by sample = ?
a = let initial activity of the sample = 100
a - x = amount left after decay process = 12.5
Now put all the given values in above equation, we get
Therefore, the time required for decay is, 84 days.