What is the percent by mass of sodium in Na2SO4? total mass of element in compound molar mass of compound Use %Element x 100
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.
Answer: The correct option is The properties of a noble gas.
Explanation: There are 7 periods in the periodic table.
The last element of each period are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn) and Ununoctium (Uuo).
- The electronic configuration for Helium is
. For He, The outermost electrons are 2.
- The electronic configuration for all the other elements is
( where, n = 2, 3, 4, 5, 6 and 7 respectively). For all the other gases, the outermost electrons are 8.
All these elements have stable electronic configuration and are not reactive in nature. Hence, they are considered as noble gases.
Therefore, the last element of each period always have the properties of a noble gas.
Answer:
A concentrated solution is one that has a relatively large amount of dissolved solute. A dilute solution is one that has a relatively small amount of dissolved solute.
Hey there!:
H is always +1 so the H's have a +3 charge.
O is always -2 so the O's have a -8 charge .
Now, suppose oxidation state for P = X , then :
+3 + X + (-8) = 0 (because of neutral molecule)
x = 8 - 3
x = + 5
So, X = +5 oxidation state.
Answer C
Hope that helps!
