1.2 in still water would be 1.2-0.5 upstream
0.7 ups
1.7 downs
Answer:
C. Surface area
Explanation:
The rate of chemical reaction depends on various factors such as:
- concentration and pressure
- nature of reactants
- temperature
- surface area
- presence of catalyst, etc.
Effect of surface area of reactants: the rate of a chemical reaction can be increased by increasing the the area of contact of the reacting substances. This is especially important when one or more of the reactants are solids., because only the particles of the solid that are exposed are able to take part in the reaction at each instant of time. Therefore, the greater the surface area of the solid reactant particles the faster the reaction.
The surface area of solid reactants can be increased by grinding or pelletizing, thus allowing for a greater contact between the reacting particles,
The instance in which one of the solid reactants was treated in a coffee grinder before adding to the reaction container is one way of increasing the surface area of a reactant.
Question 17:
At point A, the snowboarder is on the point of moving and the potential energy would be at its maximum (the particle has to work against the force of gravity). The kinetic energy is zero since the snowboarder is not yet moving (has no velocity).
Question 18:
At point C, the kinetic energy will be zero and the potential energy will be minimum. As the snowboarder moves from point C to B, there will be a transfer between the kinetic energy to the potential energy. At point B, the potential energy will be back to maximum.
Answer:
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance.
