Answer:
Calcium (Ca²⁺)
Explanation:
Calcium is very important mineral, found in teeth and bones primarily.
It is needed for the strong bones.
It is very important to maintain the bones in order to support our skeleton.
In our body it is also important to carry out other functions like in muscles, nerve function and also for heart.
If our diet is not full of calcium, the calcium deficiency may occur which leads to the weakening of bones and cause fracture.
The dietary source of calcium includes:
Yogurt, cheese, milk
beans such as peas, peanuts.
fishes
almonds, oranges, molasses
This is true because -
In order for any reaction to happen, those particles must first collide. This is true whether both particles are in solution, or whether one is in solution and the other a solid. If the concentration is higher, the chances of collision are greater.
Answer: 498.51mmHg
Explanation:
First let us analyse what was given from the question:
T1 = 425K
T2 = 275.15K
P1 = 770 mmHg
P2 =?
Using the general gas equation
P1V1/T1 = P2V2/T2
But we were told from the question that the volume is constant. So, our equation becomes:
P1/T1 = P2/T2
770/425 = P2 /275.15
Cross multiply to express in linear form:
P2 x 425 = 770 x 275.15
Divide both side by 425, we have:
P2 = (770 x 275.15) /425
P2 = 498.51mmHg
Answer:
Yes, a chemical change occurs.
Explanation:

CaSO4 is insoluble in the water, so a chemical reaction or chemical change occurs.
250.00 mL) x (1.0 M ) / (2.5 M) = 100 mL
So take 100 mL of 2.5 M HCl and dilute it to 250 mL.