Charles knows that adding salt to water causes the freezing point of water to be lowered, but he wants to know if rock salt affects the freezing point more than table salt. Charles performed an investigation in his classroom in which he measured the freezing point of 250 mL of water. He used this measurement as his control. Then, he dissolved equal amounts of rock salt and table salt in two identical 250 mL beakers of water. Finally, he measured the freezing points of each beaker of water, analyzed his results, and formed a conclusion.

What type of investigation did Charles perform?

this protocol provides a detailed procedure for total protein extraction for western blot analysis from achieved samples following trizol isolation of rna.

hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.  

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.