Answer:
increase
Explanation:
At the skate park when a skateboarder wants to skate down a ramp, the skate boarder wishes to move faster and with speed so that it help him to skate more time. This can only be achieved if the all the forces acting on him will increase as he skates down the ramp without much of the frictional force acting on the wheels of the skate board. The less friction force acts on the wheel, the more he can skate with more speed.
Thus, the skateboarder wants the force to be increase that is acting on him.
Answer:
d) cut the large sized Cu solid into smaller sized pieces
Explanation:
The aim of the question is to select the right condition for that would increases the rate of the reaction.
a) use a large sized piece of the solid Cu
This option is wrong. Reducing the surface area decreases the reaction rate.
b) lower the initial temperature below 25 °C for the liquid reactant, HNO3
Hugher temperatures leads to faster reactions hence this option is wrong.
c) use a 0.5 M HNO3 instead of 2.0 M HNO3
Higher concentration leads to increased rate of reaction. Hence this option is wrong.
d) cut the large sized Cu solid into smaller sized pieces
This leads to an increased surface area of the reactants, which leads to an increased rate of the reaction. This is the correct option.
Just as a dozen is 12 of something, a mole is about 6.02 * 10^23 of something .
Answer: 250 ml of stock solution with molarity of 12.0 M is measured using a pipette and 250 ml of water is added to volumetric flask of 500 ml to make the final volume of 500 ml.
Explanation:
According to the dilution law,

where,
= concentration of stock solution = 12.0 M
= volume of stock solution = ?
= concentration of diluted solution= 6.00 M
= volume of diluted acid solution = 500 ml
Putting in the values we get:


Thus 250 ml of stock solution with molarity of 12.0 M is measured using a pipette and 250 ml of water is added to volumetric flask of 500 ml to make the final volume of 500 ml.
he is a good scientist because he postulated that chemical reactions resulted in the rearrangement of the reacting atoms