True statements:1) deltaH for endothermic reaction is positive3) when the energy is transferred as heat from system to surroundings, deltaH is negative.6) A combustion reaction is exothermic .False statements:2) deltaH for exothermic reaction is positive. actually it is negative4) when the energy is transferred as heat from surroundings to system, deltaH is negative. actually it is positive5) the evaporation of water is an exothermic process. actually it is an endothermic process.

Delta H for endothermic reaction is positive-True. This is because an endothermic reaction absorbs heat energy, therefore more energy is retained inside the product of the reaction system than the reactants, as the value of deltaH is greater than Zero.

Delta H for an exothermic reaction is positive. This is false. Because in an exothermic reaction  heat is liberated to the  surrounding environment. therefore the value of thus the outer environment contains more energy than the internal environments, thus the enthalpy of the reactants is greater than that of the products.

when the energy is transferred as heat from system to surroundings, deltaH is negative. True . This is true because the surrounding environment gain heat energy, (positive)while  the system loses it,(negative) therefore delta H is negative.

when the energy is transferred as heat from surroundings to system, deltaH is negative.  False. This is  positive, because now the environments loses heat, (negative) while the systems gains heat,( positive) therefore delta H of the system is positive. endothermic

the evaporation of water is an exothermic process-False, This is an endothermic reaction in which water molecules need to gain heat energy from the surrounding environments to increase the average kinetic energy  of collusion to escape the intermolecular forces to escape as steam.

Combustion reaction is exothermic. True., because heat energy is transferred to the surrounding from the internal system. The energy needed for the formation  of  new bonds in the products is higher than the energy for breaking of original bonds in the reactants. Thus more heat is liberated.

Explanation:

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.