Answer:
A chemical change because a temperature change occurred, the solid disappeared and a gas was produces
Explanation:
Magnesium reacts with hydrochloric acid releasing energy, and leading to the formation of magnesium chloride and hydrogen gas. This is represented by the equation below:
Mg₍s₎ + 2HCl₍aq)⇒ MgCl₂₍aq₎ + H₂₍g₎
NaHCO3 = No. of atoms are 1 sodium + 1 Hydrogen + 1 carbon + 3 oxygens = 6 atoms per molecule.
so a total of 3 oxygens
Answer:
ELEMENTS
COMPOUNDS
Elements are made up of one kind of atoms.
Compounds are made up of two or more kinds of atoms.
Elements cannot be broken down into simpler substances by any physical or chemical method.
Compounds can be broken down into simpler substances by chemical methods.
Elements have their own set of properties.
Properties of a compound differ from those of their elements.
Examples: Hydrogen, Oxygen
Examples: Water, Sodium chloride
Answer: high iridium levels in a 66- million-year-old clay layer in Denmark and Italy
Explanation: