Is it an atomic model? I'm not really sure
delete please .....................................
Answer:
177253.125hrs
Explanation:
Given parameters:
Number of hours spend per day on phone = 6.25hrs
Unknown:
Average hours pend by an average American if they lived for 77.7yrs
Solution:
Let us find the number of hours an average American spends on their phone per year;
there are 365days in a year
Number of hours = 365 x 6.25 = 2,281.25hrs
Now, if they lived for 77.7yrs;
They will spend = 77.7 x 2,281.25 = 177253.125hrs
Answer:
1 mole of propane combines with 5 moles of oxygen gas to produce 3 mole of carbon dioxide and 4 moles of water.
Explanation:
The word equation for the combustion of propane can be obtained from the chemical equation;
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
The word equation is therefore:
1 mole of propane combines with 5 moles of oxygen gas to produce 3 mole of carbon dioxide and 4 moles of water.
For such a combustion reaction, carbon dioxide and water are produced in the process.
Answer: -
0.1 ml of bleach should be added to each liter of test solution.
Explanation:-
Let the volume of bleach to be added is B ml.
Density of stock solution = 1.0 g/ml
Mass of stock solution = Volume of stock x density of stock
= B ml x 1.0 g/ml
= B g
Amount of NaOCl in this stock solution = 5% of B g
=
x B g
= 0.05 B g
Now each test solution must be added 5 mg/l NaOCl.
Thus each liter of test solution must have 5 mg.
Thus 0.05 B g = 5 mg
= 0.005 g
B = 
= 0.1
Thus 0.1 ml of bleach should be added to each liter of test solution.