TIMED QUIZ HELP What is the molar mass of Na2CO3?
60.0 g/mol
106.0 g/mol
118.0 g/mol
141.0 g/mol

Answer is in the photo. I can't attach it here, but I uploaded it to a file hosting. link below! Good Luck!

cutt.ly/nz6VGda

i dont know

this was just a light-hearted joke plz dont delete

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.