<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We calculate as follows:
2.30 g NH3 (1 mol / 17.03 g ) (</span>6.022 x 10^23 molecules / 1 mol ) = 8.13x10^22 molecules
<span>The oldest of those supercontinents is called Rodinia and was formed during Precambrian time some one billion years ago. Another Pangea-like supercontinent,
Pannotia, was assembled 600 million years ago, at the end of the
Precambrian. Present-day plate motions are bringing the continents
together once again.</span>
Answer:
76
Explanation:
Alpha decay is one of the most basic forms of radioactive decay. It has an atomic mass of 4 and a proton number of two.
Undergoing an alpha decay will decrease the atomic mass by four and the atomic number by two.
In this particular question, we are particular about the atomic number. The atom has an atomic number of 78. So taking 2 off this gives 76
Answer:
Explanation:
The formula for efficiency is
Data:
Useful energy = 3 J
Energy input = 30 J
Calculation:
