Step 1 - Remembering the law of mass conservation
As stated by the law of mass conservation, in a chemical process no atoms can be created or destroyed. Consequently, the mass of the system will not change: the sum of the masses of reactants will be exactly equal the sum of the masses of products.
Step 2 - Using the law of mass conservation to understand the problem
The law of mass conservation therefore guarantees that, if we are mixing 7.2 g of C with 19.2 g of O, we will form 7.2+19.2 g of whatever is the product. Therefore we will form 26.4 g of product, which will be either CO or CO2.
Step 3 - Using mass percentage to find the correct product
Since we already know what will the mass of the product be, we can calculate the percentage of C in the product:
Now, let's calculate the percentage of C in both CO (28 g/mol) and CO2 (44 g/mol), remembering that the molar mass of C is 12 g/mol:
We can see that in CO2 the amount percent of C is exactly the same as we have calculated for the unknown product of this reaction. Therefore, the product is CO2.
Answer:
Explanation:
1. Rounding
2 0<u>83 193</u> cm
You want to round to two significant figures.
You replace all the underlined digits (all those after the first two digits) with zeroes.
The rule is: If the first figure dropped (8) is greater than 5, increase the last figure kept (0) by 1.
Then, 2 0<u>83 193</u> cm becomes 2 100 000 cm
2. Converting to scientific notation
A number in scientific notation has the form
N × 10ⁿ
where N is a decimal number called the mantissa and n is an integer called the exponent.
We must have 1 ≤ N < 10
(a) Determine the mantissa
Move the decimal place to the left to create a new number between 1 and 10.
2 1<u>00 000</u> ⟶ 2.1<u>00 000</u>; N = 2.1
(b). Determine the exponent.
The exponent is the number of times you moved the decimal to get the mantissa.
You moved the decimal six places to the left, so the exponent n = 6.
(c). Write the number in scientific notation
The answer is b this is your answer
Both are in gas phase. That's the equilibrium attained.