Answer:
increases the frequency of particle collisions
Explanation:
One factor upon which the rate of reaction depends is the surface area of reactants.
According to the collision theory, reactions occur when reactant particles having the required (activation) energy collide with each other, this collision is inelastic. However, collision of particles having energies less than the activation energy results in elastic collisions and no chemical reaction.
The more the exposed surface area of reactants, the greater the number of particles that come into contact with each other and the more the chances of frequent effective collisions that lead to reaction.
Thus, powdered zinc reacts faster with hydrochloric acid than zinc strips
Answer : It is only one of those ancient sights which still exist and gives ancient antiquity to the great pyramid in Egypt. It is believed that the pyramids are the definition of prayers that still remains in the heart of the local people.
It is also one of seven wonders of the world that is under world heritage. Pyramids where only found in Egypt and nowhere else.
Explanation:
When a metal replaces another metal in solution, we say such a reaction has undergone a single displacement reaction.
In such a reaction, metal higher up in the activity series replaces another one due to their position.
To known the metal or metals that will replace the given copper, we need to reference the activity series of metals.
Every metal higher than copper in the series will displace copper from the solution.
So, there metals are: potassium, sodium, lithium, barium, strontium etc.
Answer:
Cost to supply enough vanillin is 
Explanation:
Threshold limit of vanillin in air is
per litre means there should be
of vanillin in 1L of air to detect aroma of vanillin.

So, 
So amount of vanillin should be present to detect = 
As cost of 50 g vanillin is
therefore cost of
vanillin = 
Answer:
12
Explanation:
If GT bisects BN at point G, then point G would be in the middle of BN. So, since Bg and NG have to be equal and add up to 24, then the answer is 12.