The Equation is CaH2(s)+2H2O(l)-->Ca(OH)2(aq)+2H2(g)
so,
moles of H2 generated = PV / RT
R = 62.363 L Torr K−1 mol−1
number of moles = 814 * 53.5 / 62.363 * 293
= 2.38 moles
looking at the equation these came from 2.38 /2 moles of CaH2 or 1.19 moles
Molar mass of CaH2 is 42.0943 g/mol
so mass of CaH2 = 1.19 X 42.1 = 50.01g
9.75 x 10^5
A number in scientific notation has the form <em>a x 10^b</em> where
• a is the <em>coefficient</em>
• b is the <em>exponent</em>
Here are the steps to convert a number greater than 1 to scientific notation.
a) Find the coefficient
Put the decimal point after the first digit and drop the trailing zeroes
<u>9.75</u> 000
The coefficient is 9.75
.
b) Find the exponent
Count the number of digits after the first digit.
In 975 000 there are five digits after the 9. Therefore, the exponent is 5.
c) Write the number
We write 975 000 as 9.75 x 10^5.
Answer:
Explanation:
A <em>combustion reaction</em> is the reaction with oxygen along with the release of energy in form of heat or light.
Organic compounds (like CH₄) undergo combustion forming water and CO₂.
The combustion reaction of CH₄ is:
Hence, the first equation from the choices is not showing the combustion reaction of CH₄.
Not only organic compounds can undergo combustion. Metals and no metals can undergo combustion, i.e. metals and no metals can react with oxygen releasing light or heat.
The reaction of copper and oxygen (second choice) is a combustion reaction:
The formation of water (2H₂ + O₂ → 2H₂O) is other example of a combustion reaction where no organic compounds are involved.
On the other hand, the other two equations from the choice list are not reactions with oxygen, so they do not show combustion reactions.
Answer: With each input, there is an output, a recipe requires certain ingredients, and certain amounts of each. A recipe calls for measurements, missing something can ruin it, just like a chemical formula, take something out or add something else, you get something completely different. when putting things together to make something you have to make sure what your putting in, will give you the product you want as the output.
Explanation:
