Determine whether each observation describes a chemical or a physical property. 1. When a piece of sodium metal is placed in a test tube with water, the sodium zees and bubbles of gas are formed. 2. When table salt is added to water in a test tube, the table salt dissolves. . 3. When a glass marble is heated and then quickly cooled, it shatters. *

1.Sodium metal reacts rapidly with water to form a colorless solution of sodium hydroxide ... strip is placed in a test tube containing 5 mL of hydrochloric acid, HCl. Both liquids ... If it fizzes and bubbles

2.When salt is mixed with water, the salt dissolves because the covalent bonds of water are stronger than the ionic bonds in the salt molecules.

3.When platinum is heated, then cooled to its original state, we say this is a physical change. 19. ... Scratches glass. Sour taste ... A bar of lead is more easily bent than is a bar of aluminum of the same size.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !