Answer:
10.9%.
Explanation:
The first thing to do in order to solve this question is to Determine the value for the volume of the the cube. This can be done by taking the cube root of the length of the cube;
The volume of the cube = (length of the cube)^3 = length × length × length = 1.72 × 1.72 × 1.72 =( 1.72)^3 = 5.09cm^3.
The next thing you do is to Determine the exponential density, the can be done by using the formula below;
The exponential density = mass/ volume = 55. 786/ 5.09 = 10.96 g/cm^3.
Therefore, the percent error = (true density of the cube - exponential density of the cube)÷ true density of the cube × 100.
Hence, the percent error = 12.30 - 10.96/12.30 × 100 = 10.9%.
<u>Answer:</u> The additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
<u>Explanation:</u>
To calculate the mole percent of a substance, we use the equation:
Mass percent means that the mass of a substance is present in 100 grams of mixture
To calculate the number of moles, we use the equation:
We require the molar masses of Z and X to calculate the mole percent of Z and X respectively
Hence, the additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
Single type of atom builds a single atom
Answer:
8.33mol/L
Explanation:
First, let us calculate the molar mass of of formaldehyde (CH2O). This is illustrated below:
Molar Mass of CH2O = 12 + (2x1) + 16 = 12 + 2 + 16 = 30g/mol
Mass of CH2O from the question = 0.25g
Number of mole CH2O =?
Number of mole = Mass /Molar Mass
Number of mole of CH2O = 0.25/30 = 8.33x10^-3mole
Now we can calculate the molarity of formaldehyde (CH2O) as follow:
Number of mole of CH2O = 8.33x10^-3mole
Volume = 1mL
Converting 1mL to L, we have:
1000mL = 1L
Therefore 1mL = 1/1000 = 1x10^-3L
Molarity =?
Molarity = mole /Volume
Molarity = 8.33x10^-3mole/1x10^-3L
Molarity = 8.33mol/L
Therefore, the molarity of formaldehyde (CH2O) is 8.33mol/L
Since we're talking about a chain reaction, I think this would be a) self-sustaining. Chain reactions are not usually described as "weak" and can be highly explosive depending upon the compounds (think Uranium!).
The first (artificial) self-sustaining nuclear reaction is attributed to Enrico Fermi in 1942. Here's a bit of history:
http://www.atomicarchive.com/History/firstpile/firstpile_01.shtml
