How are isotopes defined? forms of different elements that have the same number of neutrons in each atomforms of different elements that have the same number of protons in each atomforms of the same element that differ in the number of neutrons in each atomforms of the same element that differ in the number of protons in each atom?

Which of the following methods uses the decay of atomic particles in an object to find its exact age? a. fossil dating b. geologic dating c. radioactive dating d. relative dating

Sarah wants to know where in her garden chamomile would grow the best. she thinks chamomile will grow best in the corner of the garden that gets the most sunlight. to test her hypothesis, she decides to plant several groups of chamomile in her garden as an experiment. which of the following variables will sarah need to measure to know which group of plants grew best? a. the location of the plants b. the type of plants c. the height of the plants d. the amount of water she gives the plants

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon