The number 16 next to the elemental symbol of Nitrogen
which is N indicates the mass number of the element. Now the atomic number of N
is 7, this is also equal to the number of protons or electrons in the nucleus. So
the balance is 16 – 7 = 9 which is being occupied by the neutrons. Therefore
the number of neutrons is:
<span>9</span>
Answer:
Na₂CO₃ · 10H₂O
Explanation:
The formula for sodium carbonate hydrate is:
Na₂CO₃ · xH₂O
The unknown "x" is the number of water molecules contained in the hydrate.
To find "x" we have to use the hydrogen percentage in the sample, 7.05 % H.
First we calculate the molecular weight of Na₂CO₃ · xH₂O:
molecular weight of Na₂CO₃ · xH₂O = 23 × 2 + 12 + 16 × 3 + 18x
molecular weight of Na₂CO₃ · xH₂O = 106 + 18x g/mole
Now we devise the fallowing reasoning tanking in account 1 mole of Na₂CO₃ · xH₂O:
if in 106 + 18x grams of Na₂CO₃ · xH₂O we have 2x grams of hydrogen
then in 100 grams of Na₂CO₃ · xH₂O we have 7.05 grams of hydrogen
106 + 18x = (100 × 2x) / 7.05
106 + 18x = 28.4x
106 = 28.4x - 18x
106 = 10.4x
x = 106 / 10.4
x = 10.2 ≈ 10
The formula for the washing soda is Na₂CO₃ · 10H₂O.
Answer:
The formation of AN OXIDE
Explanation:
A combustion reaction is a chemical reaction which involves the burning of an hydrocarbon in oxygen
<h2>
<u>A</u><u>n</u><u>s</u><u>w</u><u>e</u><u>r</u><u>:</u><u>-</u></h2>
<em>The female part is the pistil. The pistil usually is located in the center of the flower and is made up of three parts: the stigma, style, and ovary. The stigma is the sticky knob at the top of the pistil. It is attached to the long, tubelike structure called the style.</em>
<h3>
<em><u>H</u></em><em><u>o</u></em><em><u>p</u></em><em><u>e</u></em><em><u> </u></em><em><u>I</u></em><em><u>t</u></em><em><u> </u></em><em><u>W</u></em><em><u>i</u></em><em><u>l</u></em><em><u>l</u></em><em><u> </u></em><em><u>H</u></em><em><u>e</u></em><em><u>l</u></em><em><u>p</u></em><em><u> </u></em><em><u>Y</u></em><em><u>o</u></em><em><u>u</u></em><em><u>!</u></em></h3>
Moles XeF6 = 10.0g/ 245.28 g/ mol=0.0408
The ratio between F2 and XeF6 is 3:1
Moles F2 required = 3 x 0.0408=0.122
Mass F2 = 0.122 mol x 37.9968 g/ mol=4.64g