9
Explanation:
cause 2 + 2 is equal to 9
Answer:
Exothermic reaction: In exothermic reaction, energy is transferred to the surroundings, and the surrounding temperature increases, this is known as exothermic reaction. In other words energy exits in exothermic reaction. Some example of exothermic reactions are:
1) Neutralisation reaction.
2) Combustion reaction.
3) Some oxidation reaction.
Endothermic reaction: In endothermic reaction, energy is taken in from the surrounding, and the surrounding temperature decreases, this is known as endothermic reaction. In other words energy enters in endothermic reaction. Some example of exothermic reactions are:
1) Thermal decomposition.
2) Reaction between citric acid and sodium hydrogen carbonate.
Answer:
Curd is acidic in nature, because an acidic substance has less value of pH. A milkman adds a very small amount of baking soda to fresh milk. Why does he shift the pH of the fresh milk from 6 to slightly alkaline? Answer: By making the milk more alkaline, it takes more time to turn into curd.
An element is all the same thing. Pure, if you will.
The first one is definitely an element. The second would be a compound (it's atoms are different colors). I would say the last one is an element, since it has ll the same color of atoms.
I hope this helped you! If you have anymore questions, feel free to ask me.
B the heart muscle gets too little oxygen