Answer:
True => ΔH°f for C₆H₆ = 49 Kj/mole
Explanation:
See Thermodynamic Properties Table in appendix of most college level general chemistry texts. The values shown are for the standard heat of formation of substances at 25°C. The Standard Heat of Formation of a substance - by definition - is the amount of heat energy gained or lost on formation of the substance from its basic elements in their standard state. C₆H₆(l) is formed from Carbon and Hydrogen in their basic standard states. All elements in their basic standard states have ΔH°f values equal to zero Kj/mole.
Answer:
The answer is below
Explanation:
The separation technique is used for separating immiscible liquids.
When separating, the stopper has to be removed when draining the lower layer so as to prevent a vacuum. If vacuum is allowed, the draining rate will reduce and stop.
The liquid should be mixed by shaking the funnel and then opening the stopcock so as the vent out gases.
When near interface between the layers, you should set your eye level so that you do not drain up to the second layer.
After completely draining the first layer, the second layer should be collected in a new flask.
After mixing the solutions in a separatory funnel, the stopper should be removed and the liquid should be mixed thoroughly and the layers allowed to separate. When you get close to the interface between the layers, get eye level with the funnel and slow the draining until the first layer is collected. Switch to a new flask to collect the second layer.
Yes, Ionic bonds do not share electrons. Polar covalent bonds share electrons they just share them unevenly due to the polarity.
Answer: Biological Magnification
Explanation:
Organisms acquire toxic substance from the environment along with nutrients and water. Some of the toxins are metabolized and excreted, but others accumulate in specific tissues, especially fat. One of the reasons accumulated toxins are particularly harmful is that the become more concentrated in successive trophic level of the food web, this is the process of biological magnification.
Magnification occurs because the biomass at any given level is produced from a must larger biomass ingested from the level below. Thus the top-level carnivores tend to be the organism most severely affected by toxic compounds in the environment.
Examples of toxins that demonstrate biology magnification are chlorinated hydrocarbons, and many pesticides.
SEAgel (Safe Emulsion Agar gel) is one of a class of high-tech foam materials known as aerogels.
