I think it's option C and option D but if you can only choose one answer then I think it's option C
Answer:
All around you there are chemical reactions taking place. Green plants are photosynthesising, car engines are relying on the reaction between petrol and air and your body is performing many complex reactions. In this chapter we will look at two common types of reactions that can occur in the world around you and in the chemistry laboratory. These two types of reactions are acid-base reactions and redox reactions.
Explanation:
I believe the answer is B. Definitely not D or A, and C doesn't makes sense.
Answer:
This is math?
Explanation:
I dont know how to do this sorry
Answer:
This question is incomplete but the missing part is in the picture attached.
Explanation:
A mixture of silicon oxide, ammonium chloride and sodium chloride were to be separated. Three separating techniques were used in the experiment; sublimation, decantation and evaporation.
Sublimation is the process in which a substance changes from solid to gas without passing through the liquid phase. <u>Ammonium chloride (NH₄Cl) is a substance that has the ability to sublime</u> and thus was separated first through this property before adding water to the remaining constituents (silicon oxide and sodium chloride) of the mixture. After the addition of water to the mixture, <u>sodium chloride dissolves in this water while silicon oxide does not dissolve in water</u>. The mixture is then left to stand for some minutes so the <u>undissolved sand can settle at the bottom of the mixture</u> and the <u>dissolved salt water can be decanted out</u> so as to have the silicon oxide left in the jar.
The <u>salt solution decanted will have to be evaporated to dryness</u> (to remove the added water) so as to have the solid salt back.