Answer:
number of protons plus the number of electrons in an atom
Answer: There are various indicators like litmus paper, phenolphthalein, universal indicator etc. that changes its colour to show the difference between acid and alkali.
The mass of magnesium should be less than 0.09g to enable a faster reaction rate. Magnesium reacts to form a white coating around it which stops the reaction. The lesser the gram the faster the reaction before the coating is formed. It is also advisable to use magnesium fillings to increase the rate of reaction.
Iron becomes rusted especially in damp air but never in a dry air, this is one of the many unique characteristics of iron. Iron is also ductile and malleable. It is found in the seventh group of the periodic table. It has four different and unique crystalline forms and completely dissolves in dilute acids. The two chemical compounds that can be found or made from iron are the bivalent iron also known as ferrous and the trivalent iron or known as ferric compounds.