The answer is 0.5010
Number of moles (n) is equal to the quotient of mass (m) and molar mass of a sample (Mr):
n = m/Mr
We have:
n = ?
m = 40.10 g
Mr = 80.0432 g/mol
n = 40.10 g : 80.0432 g/mol = 0.5010
<span>40.10 has 4 significant digits,
</span><span>80.0432 has 6 significant digits.
Since 4 is less than 6, we choose 4 </span>significant digits
The atomic cation with +1 charge with the following configuration:
1s22s22p63s23p6
Is Potassium (K+), remember potassium have 19 electrons in its neutral state, when if losses one electrons it becomes + with one less electron, meaning it will have 18 electrons as a cation.
There are 2 electrons in 1s orbital as it can be seen from the electron configuration.
Answer:
A.
Explanation:
You should NEVER eat or drink anything in a lab area. You never know what chemicals or gases are in the lab, and they can harm you.
Wearing a drawstring hoodie won't protect you from chemicals.
Don't wait to clean up chemicals, immediately get a teacher and clean it up (follow the teachers instructions). You never know what has spilled, and if it is harmful or not, or if there is a certain procedure to clean it up.
Don't change the equipment in the middle of an experiment. This can tamper with your results, and depending on what you are working with, this can be dangerous.