A standard solution is a solution (in this case sodium hydroxide) whose concentration (molarity) is known very precisely. <span>The molarity of the sodium hydroxide solution cannot be determined accurately because s</span>olid sodium hydroxide is highly hygroscopic (absorbs water from the air) and cannot be accurately weighed. Sodium hydroxide form sodium carbonate because it absorbs carbon
dioxide from the air.
Ok so, it all comes down to basically how nice the teachers are? Go to them and ask them personally if they'd take any late work or makeup work. Also ask (but in a very kiss butt way) if there was any chance theyd be willing to give you extra credit. The key to doing this is like basically just begging them and being super apologetic. Be fake and see if it gets you anywhere?
Answer:
Question 1: -7.3ºC
Question 2: 67.50%
Explanation:
Question 1:
For different reasons a thermometer can not give the exact temperature that it is measuring, such as incorrect calibration. So the thermometer will have an error, and for this, we can have a thermometer correction, doing experiments with a substance that we know the temperature. In this question that substance was benzoic acid.
The thermometer correction (Tc) is the temperature that was measured less the real temperature, so:
Tc = 115.1 - 122.4 = -7.3ºC
It means that the temperature given by the thermometer is 7.3ºC less than the real.
Question 2:
Recrystallization is the process of transforming the liquid in its solid form (crystals). So, the sample of 4.00 grams of benzoic acid, there'll be water or other impurities. The total benzoic acid given was 2.70 grams, so its percentage will be:
(mass of acid/ total mass)x100%
(2.70/4.00)x100% = 67.50%
Answer :
A.) Kinetic energy
Explanation:
When work is either added to or taken away from a system, it forces the <u>kinetic energy</u> to change.
The work-energy theorem states : change in <u>kinetic energy</u> of an object is <u>equal</u> to the <u>work done on the object</u>
[ I took the quiz already on Edgenuity and received 100% ]
Hope this helped ! :)
