True. Each contour line on a topographic map represent a certain elevation; the closer they are, the steeper the surface is. All points on a contour line are the same elevation.
Answer:
6,613 M
Explanation:
Dilution is the process of reducing the concentration of a solute in solution, mixing initial solution with more solvent.
The concentration of Solution B is:
23,881 M × = 9,552 M
Because the initial eight parts are diluted to 12+8 parts.
Thus, concentration of solution C is:
9,552 M × = 6,613 M
I hope it helps!
<h2>C</h2>
Explanation:
The atomic number of S is 
So,number of electrons in S is 
The electronic configuration of S is 
The orbital electronic configuration of S is 
So,the number of orbitals involved is 9.
Answer:25.3 g of KNO₃ contain 0.25 moles.
Explanation:
Answer:
The mass of Na₂O that can be produced by the chemical reaction of 4.0 grams of sodium with excess oxygen in the reaction is 5.39 grams.
Explanation:
You know the balanced reaction:
4 NA + O₂ ⟶ 2 Na₂O
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) react and are produced:
- Na: 4 moles
- O₂: 1 mole
- Na₂O: 2 moles
Being:
the molar mass of the compounds participating in the reaction is:
- Na: 23 g/mole
- O₂: 2*16 g/mole= 32 g/mole
- Na₂O: 2*23 g/mole +16 g/mole= 62 g/mole
Then by stoichiometry of the reaction they react and are produced:
- Na: 4 moles* 23 g/mole= 92 g
- O₂: 1 mole*32 g/mole= 32 g
- Na₂O: 2 moles* 62 g/mole= 124 g
Then you can apply the following rule of three: if 92 grams of Na produce 124 grams of Na₂O, 4 grams of Na, how much mass of Na₂O does it produce?

mass of Na₂O=5.39 g
<em><u>The mass of Na₂O that can be produced by the chemical reaction of 4.0 grams of sodium with excess oxygen in the reaction is 5.39 grams.</u></em>