Answer:
Harmony is correct, because Mendeleev’s model made predictions that came true.
Explanation:
Mendeleev published periodic table.
Mendeleev also arranged the elements known at the time in order of relative atomic mass, but he did some other things that made his table much more successful.
Our answer is : Harmony is correct, because Mendeleev’s model made predictions that came true.
Answer:
The average atomic mass of boron is found to be
10.80
Explanation:
also u answered it urself
7 moles of oxygen are in the sample.
According to the chemical formula, each mole of nickel tetracarbonyl contains 4 moles of C atoms. Simply convert it into a fraction by putting the original solution in the denominator and the diluted solution in the numerator if you need to determine the concentration ratio between two solutions. The V/n ratio for each gas must be the same if the two gases are at the same temperature and pressure. The volume ratio of two gases at the same temperature and pressure is equal to their molar ratio. The mole ratio of C to O is 1 : 1
Learn more about moles here brainly.com/question/10873665
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<h3>Further explanation
</h3>
Given
Atomic symbol
Required
Atomic composition
Solution
Atomic number = number of protons = number of electrons
Mass Number (A) is the sum of protons and neutrons
Number of protons and Number of Neutrons in nucleus
Number of electrons in the shell
From the picture:
protons = 3
neutrons = 4
electrons = 3
atomic number = protons = electrons = 3
mass number = protons + neutrons = 3+4 = 7
Yes oxygen is an element it is
the 8th element
the second period
16th group
noble gas configuration [He]2s^22p^4