The first thing you do before performing anything in the laboratory is to read the procedure and prepare the materials needed. Next, if you already have the solution where you are supposed to take your 20 mL sample, then have it near you. Then, prepare a volumetric flask (750 mL) and a 20-mL pipette. Wash the pipette 3 times with the sample solution. If your diluent is water, wash the flask 3 times with water. Now, get 20 mL of sample from your parent solution, then add it to the flask (previously washed with water). Finally, add water until the mark in the flask and make sure that the water added is up to the mark based on the lower meniscus reading to be accurate in the amount inside the flask. <span />
It’s C I think and I’m not sure
The molecules in gas are farther apart and have more room to bounce around than liquid
Answer:
B) K⁺, Sr²⁺ , O²⁻
Explanation:
Potassium is present in group one. It is alkali metal and have one valance electron.Potassium need to lose its one valance electron and form cation to get complete octet.
That's why it shows K⁺.
Sr is alkaline earth metal. It is present in group two. It has two valance electrons. Strontium needed to lose its two valance electrons and get stable electronic configuration.
When it loses its two valance electrons it shows cation with charge of +2.
Sr²⁺
Oxygen is present in group 16. It has sex valance electrons. It needed two more electrons to complete the octet. That's why oxygen gain two electron and form anion with a charge of -2.
O²⁻