I can help say like gas is steaming from a pot like you cooking on the gas is being conserved after it evaporates and liquid if you drink water it’s going into your body so it’s being conserved and solid said like i have a brick and you throw it and it breaks it had been conserved because it’s broken
12.5% of strontium-90 would remain in a sample after three half-lives have passed. Half-life automatically means 50% of the original amount would remain.
Answer:
A. Group 4
Explanation:
Also called carbon family or the tetrels
Answer:
The average mass of all isotopes of the element
Explanation:
Mass number is most similar to the average mass of all isotopes of the element. Mass number = number of protons +number of neutrons, and it is a mass of one of the type of isotope.
A chemical change refers to a process by which a substance becomes a new and different substance. The fizzing of the tablet (also called effervescence) indicates that a gas is being produced. The gas being produced is an indication of a chemical reaction. A chemical reaction is a process in which substances undergo physical and chemical changes that result in the formation of new substances that have different properties.
