Answer:
Question 8, I think is C describe CR. Question 7 is Chemical reactions produce new substances
Explanation:
Half-life refers to the time taken for half of the atoms in a radioactive substance to decay. Therefore in 1 half-life the 80 mg of substance will reduce to 40 mg. In another half-life it will reduce from 40 mg to 20 mg, then in a third half-life from 20 mg to 10 mg. Therefore the half-life is equal to the total time taken to decay from 80 mg to 10 mg divided by 3:
t(1/2) = 36 hours / 3 = 12 hours.
Its A Natural resources are found in abundance in the US.
Answer:
1. 7.256g of NaCl
2. 47.33g of Cl2
Explanation:
2 moles of Na reacts to produce 2 moles of NaCl
8 moles of Na will still produce 8 moles of NaCl
Mass of NaCl = molar mass of Nacl/moles of Nacl
=58.5/8
=7.256g of NaCl
From the equation, 2 moles of Na reacts with 1 mole of Cl2
3/2 moles of Cl2 will react with 3 moles of Na
Mass of Cl2 = 71/1.5
=47.33g of Cl2
Answer: Temperature is an example of a quantitative variable
Explanation:
A quantitative variable is defined as :
- A variable that can assume a numerical value .
- It can be ordered with respect to either magnitude or dimensions.
- It is further classified into two types : interval scale and ratio scale.
Temperature comes under interval scale , because interval scale has no zero point.
For example : A 0° C Celsius does not interpret that there is no temperature.
Therefore , Temperature is an example of a quantitative variable.
Hence, the correct answer is "quantitative variable"