> How many valence electrons does a helium atom have?
The electron configuration of Helium is simply 1s2. We see
that its outermost shell is the s shell and it contains 2 electrons, therefore
the number of valence electrons is also 2.
> What is the formula of the ion formed when potassium
achieves noble-gas electron configuration?
Potassium has a electron configuration of [Ar] 4s1. To
have an electron configuration of only [Ar] which is a noble gas, the one electron
from 4s1 should be removed, hence:
<span>K+</span>
The number of atoms that are in 9.008 moles of carbon is
5.423 x 10^24 atoms
<u><em>calculation</em></u>
The number of atoms is calculated using the Avogadro's constant
That is According to Avogadro's 1 moles = 6.02 x 10^23 atoms
9.008 moles= ? atoms
by cross multiplication
= [(9.008 moles x 6.02 x 10^23 atoms) / 1 mole] = 5.423 x10^24 atoms
Answer:
The rate law is [B]
Explanation:
In Trials 1 and 2, the concentration of B changes and A is the same so you can see how changes in B affect the rate. In this case, 0.300/0.150=2 and 7.11 x 10^-4 / 3.56 x 10^-4= 2. Since there 2^1=2, we can say that the reaction order of B is 1.
Similarly, if we look at trials 2 and 3, the concentration of B is constant, while A is changing. In this case, the rate has not changed at all with a change in concentration of A, so this means that A has 0 order.
Therefore, the rate law is just [B].
Shampoo tubes are hollow tubes so things can be stored or used as a conducter as it is metal.
Modern atomic theory is, of course, a little more involved than Dalton's theory but the essence of Dalton's theory remains valid. Today we know that atoms can be destroyed via nuclear reactions but not by chemical reactions. Also, there are different kinds of atoms (differing by their masses) within an element that are known as "isotopes", but isotopes of an element have the same chemical properties.
Many heretofore unexplained chemical phenomena were quickly explained by Dalton with his theory. Dalton's theory quickly became the theoretical foundation in chemistry.