Answer:
The mass of 0.280 mole sample of sodium hydroxide NaOH is 11.2 grams.
Explanation:
To know the mass in grams of 0.280 moles of sample of sodium hydroxide NaOH, you must know the molar mass of the compound, that is, the mass of one mole of a substance, which can be an element or a compound.
So you know:
- Na: 23 g/mole
- O: 16 g/mole
- H: 1 g/mole
So, the molar mass of NaOH is:
NaOH= 23 g/mole + 16 g/mole+ 1 g/mole= 40 g/mole
Then the following rule of three can be applied: if in 1 mole of sodium hydroxide there are 40 grams, in 0.280 moles how much mass is there?
mass= 11.2 grams
<u><em>The mass of 0.280 mole sample of sodium hydroxide NaOH is 11.2 grams.</em></u>
Hello, Thanks for making your post on brainly!
I would say the best answer is C)Mixture
A mixer is made by combining 2 or more elements, but your not making a new element. And there are no chemical reactions happening to make a new element.
Hope this helps. Have a great day.
Answer:
A. There is more dissolved oxygen in colder waters than in warm water.
D. If ocean temperature rise, then the risk to the fish population increases.
Explanation:
Conclusion that can be drawn from the two facts stated above:
*Dissolved oxygen is essential nutrient for fish survival in their aquatic habitat.
*Dissolved oxygen would decrease as the temperature of aquatic habit rises, and vice versa.
*Fishes, therefore, would thrive best in colder waters than warmer waters.
The following are scenarios that can be explained by the facts given and conclusions arrived:
A. There is more dissolved oxygen in colder waters than in warm water (solubility of gases decreases with increase in temperature)
D. If ocean temperature rise, then the risk to the fish population increases (fishes will thrive best in colder waters where dissolved oxygen is readily available).
Q1)
We have been given the OH⁻ concentration, therefore we first need to find the pOH value and then the pH value.
pOH = -log [OH⁻]
pOH = -log (0.225 M)
pOH = 0.65
pH + pOH = 14
pH = 14 - 0.65 = 13.35
Q2)
pOH = -log[OH⁻]
pOH = -log (0.0015 M)
pOH = 2.82
pH + pOH = 14
pH = 14 - 2.82
pH = 11.18
