Answer:
See explanation
Explanation:
Precision means the reputability of measurement and accuracy means how close a measurement is to the actual value. To get the measured mass of the acetone we need to substract the mass of the bottle from the measured mass of bottle and acetone.
The mass of the bottle is 38.0015g
⇒The mass of acetone in bottle 1= 0.7783g
⇒Mass of acetone in bottle 2= 0.7780g
⇒Mass of acetone in bottle3= 0.7786g
The measured value is near to each other. ⇒ the measurements are <u>precise</u>.
To check the <u>accuracy</u> we can compare the average value to the actual mass of the acetone.
Average of the acetone measurement is (0.7783+0.7780+0.7786)/3 = 0.7783g
The percentage of difference of the average measurement to the actual mass is = {(actual value-measured value)/actual value}x100%
={(0.7791-0.7783)/0.7791}x100%
=0.10%
So we can see the difference is very small ⇒ the measurement is accurate.
This is an incomplete question, the image for the given question is attached below.
Answer : The wavelength of photon would be absorbed, 
Explanation :
From the given diagram of energy we conclude that,
Energy at ground state, A = 400 zJ
Energy of 2nd excited state, C = 1050 zJ
Now we have to calculate the energy of the photon.


Now we have to calculate the wavelength of the photon.
Formula used :

As, 
So, 
where,
E = energy of photon = 
= frequency of photon
h = Planck's constant = 
= wavelength of photon = ?
c = speed of light = 
Now put all the given values in the above formula, we get:


Therefore, the wavelength of photon would be absorbed, 
Answer:
A) They all have 12 protons.
Explanation:
Magnesium has an atomic number of 12 which means it has 12 protons. All Magnesium atoms have 12 protons, the neutrons however may differ which produces things called isotopes where the atoms have same protons but neutrons change.
Keep in mind the atomic number is unique to each element, so 12 atomic number will always be Magnesium, 1 will always be Hydrogen and so on.....
Color, phase, odor and boiling point are the physical properties. Reactivity with oxygen depends on the chemical nature of object, thus, it is not a physical property. It is a chemical property.
Answer:
B. Aluminum is a good conductor of heat
Explanation:
Physical properties are usually those that can be observed using our senses such as color, luster, freezing point, boiling point, melting point, density, hardness and odor. The Physical Properties of Aluminum are as follows: Color : Silvery-white with a bluish tint.