1. A) Bohr
2. D) When excited electrons return back to the ground state, a photon of light is emitted.
3. D) 10.812 amu
Hope this helps! :)
I think so, <span> how much of all chemistry is to do with numbers? A lot! So being good at mathematics makes a huge aspect of chemistry so much easier but if you aren't mathematical then you can work at it and become reasonably proficient at it.</span>
Answer : The measurements are both precise and accurate.
Explanation :
Accuracy : It is defined as the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 50 kg and one person weighed 48 kg and another person weighed 55 kg. Then, the weight measured by first person is more accurate.
Precision : It is defined as the closeness of two or more measurements to each other.
For Example: If you weigh a given substance five times and you get 1.8 kg each time. Then the measurement is said to be precise.
Level of precision is determined by the maximum number of decimal places.
When the level of precision is very very less, the measurement can be considered as most precise and most accurate.
As we are given the standard value of the sample is 20.000 and the values measured by the balance are, 19.995, 20.005, 20.001.
Since these three values are in the range of +/- 0.005 from one another. So, we can say that the measurements are both precise and accurate.
Hence, the measurements are both precise and accurate.
The answer would have to be letter b. Energy