Answer: The atomic mass in the periodic table is a weighted average of all naturally occuring isotopes of zinc.
Explanation: The elements consist of protons, neutrons, and electrons. Protons and nuetrons are assigned a mass of 1 amu (atomic mass unit). Electrons are too small to make a big difference in the mass, so they are assign a 0 for their amu. Since the elements consist of just these three particles, any one atom must add up to a whole number atomic mass. Zinc consists of 30 protons, by definition. A neutral atom has 30 electrons. The balance of a zinc atom is made up of neutrons. A Zn-65 atom would have 30 protons and 35 neutrons:
30 Protons = 30 amu
35 Neutrons = 35 amu
30 Electrons = 0 amu
Total AMU = 65
Any <em><u>ONE </u></em> Zn atom should have a whole number atomic mass. But zinc in the environment has isotopes of zinc - atoms that contain differing numbers of neutrons. A Zn-66 atom would have 36, instead of 35 neutrons. (P:30, N:36, E:0 = 66 amu). The atomic mass in the Periodic Table reflects the average of these isotopes as found in the environment. If the 65 and 66 isotopes were the only ones found naturally, an atomic mass of 65.38 would suggest around 60% of the atoms are Zn-65 and 40% are Zn-66. The average weight atomic mass would would be 65.40
Answer:
catalyst
Explanation:
this help toalter or speed up the rate of reaction could be the most to slow it
Air does move from high to low pressure so true
Answer:
Pure Substance
Explanation:
i just answered this question in class
