Radioactive decay is expressed by the following formula:
N₀ is the initial number of undecayed atoms.
Nt is the number of undecayed atoms remaining after time t
λ is the decay constant.
The relationship between λ and the half life time t1/2 is:
λ =
= 0.693 / 5.27 = 0.1315
Taking natural logs for both sides of the decay expression:
ln Nt = ln N₀ - λ t
ln Nt = ln 199 - (0.1315 x 20)
= 5.293 - 2.63 = 2.66
From which:
Nt = 14.29 g
Explanation:
The reaction equation will be as follows.
Calculate the amount of dissolved as follows.
It is given that = 0.032 M/atm and = atm.
Hence, will be calculated as follows.
=
=
=
or, =
It is given that
As,
=
=
Since, we know that pH =
So, pH =
= 5.7
Therefore, we can conclude that pH of water in equilibrium with the atmosphere is 5.7.
<u>Answer:</u> The chemical symbol of the compound formed is or
<u>Explanation:</u>
An ionic compound is formed when the complete transfer of electrons takes place from one element (usually metals) to another element (usually non-metals).
The element losing electron (metal) forms a positive ion known as a cation while the element gaining electron (non-metal) forms a negative ion known as an anion.
Element X has the atomic number 11 which is sodium. The electronic configuration of it is
This element will lose 1 electron to form ion of
Chlorine has the atomic number 17. The electronic configuration of it is
This element will gain 1 electron to form ion
When these two ions combine, they lead to the formation of an ionic compound having a chemical formula of or
Hence, the chemical symbol of the compound formed is or
Okay, so you need to start by finding the molar mass (grams in one mole) of nitrogen monoxide (NO).
N=14g
O=16g
So we know that NO has a molar mass of 30 grams, then just divide your given mass of 22.5 grams by the molar mass of 30 grams to find the number of molecules in your sample. The answer should be .75 molecules. Hope this helps!