Question requires a change resulting in an increase in both forward and reverse reactions. Now lets discuss options one by one and see there impact on rate of reactions.
1) <span>A decrease in the concentration of the reactants:
When concentration of reactant is decreased it will shift the equilibrium in Backward direction, so resulting in increasing the backward reaction and decreasing the forward direction. Hence, this option is incorrect.
2) </span><span>A decrease in the surface area of the products:
Greater the surface Area greater is the chances of collision and greater will be the rate of reaction. As the surface area of products is decreased it will not favor the backward reaction. Hence again this statement is incorrect according to given statement.
3) </span><span>An increase in the temperature of the system:
An increase in temperature will shift the reaction in endothermic side. Hence, if the reaction is endothermic, an increase in temperature will increase the rate of forward direction or if the reaction is exothermic it will increase the rate of reverse direction. Hence, this option is correct according to given statement.
4) </span><span>An increase in the activation energy of the forward reaction:
An increase in Activation energy will decrease the rate of reaction, either it is forward or reverse. So this is incorrect.
Result:
Hence, the correct answer is,"</span>An increase in the temperature of the system".
Explanation:
The more reactive element replaces less reactive element during chemical reaction.
Since, potassium is more reactive than beryllium. When potassium reacts with beryllium choride, it replaces beryllium and forms potassium chloride and produces beryllium.
<span>1962.252(a)
whenever the material is dropped from 20feet to any poiny lying outside the exterior wall of building, an enclosed chute of wood, or equivalent material. For the purpose of paragraph, an enclose chute is a slide, closed in all sides, through which material is placed from high plac eto lower one.
1962.252(b)
when the disposal is dropped through holes in the floor without the use of chute, the area onto which the material is dropped shall be completely enclosed with barricades not less than 42 inch high and not less than 6 feet back from the projected edge of of the opening valve. signs warning of hazards of falling material shall be posted at each level.
1962.252(c)
All scrap lumper, waste material, and rubbish shall be removed from the immediate work area as the work progresses.
1962.252(d)
Disposal of waste material or debris by burning shall comply with local fire regulation
1962.252(e)
All sovent waste, oily rags, and flammable liquid should be kept in fire resistant covered container until removed from work site.</span>
For #3 the answer is B, for #4 the answer is F, and for #5 the answer is B.