Answer:
As^3-, Se^2-, Br^-, Rb^+, Sr^2+
Explanation:
1 mol = 6.023x10^23 number of molecules (Avogadro's number)
1 : 6.023x10^23
X : 4.91x10^22
(6.023x10^23)X = 4.91x10^22
X = 4.91x10^22/6.023x10^23
X = 0.082 Moles
Chemical test to distinguish between propane and propene. (i) Bromine water test : Propane contains double bond, therefore when we pour the bromine water to propene sample, it decolouries the bromine water whereas propane which is a saturated hydrocarbon does not decolourise the bromine water.
Answer:
1.These results are accurate because the collected data is very close to the actual value.
4.These results are precise because all three trials are within a very close range.
Explanation:
Although in the ordinary language the terms precision and accuracy may be confused, in science those terms refer different properties of the measurements.
The accuracy is how close a measurement is to the true value, while the the precision refers to the reproducibility and repeatability, this is how the results show the same (close) value.
To differentiate precision and accuracy, It is very illustrative, to use the image of a throwing arrows to a target: if the arrows get close to the center of the target, then the results are accurate (close to the goal). If the arrows are not close to the cener of the target, but they are all close to each other, then the result is precise (the arrows land, approximately, in the same spot every time).
