Answer:
0.12 M hydrofluoric acid + 0.17 M potassium fluoride
Explanation:
To make a buffer, you must to have an aqueous mixture of a weak acid and its conjugate base or vice versa.
Knowing that:
0.32 M calcium chloride + 0.27 M sodium chloride: <em>is not a good buffer system </em>because CaCl₂ and NaCl are both salts.
0.35 M ammonia + 0.36 M calcium hydroxide <em>is not a good buffer system </em>because ammonia is a weak base but calcium hydroxide is a strong base
0.19 M barium hydroxide + 0.28 M barium chloride <em>is not a good buffer system </em>because Ba(OH)₂ is a strong base.
0.12 M hydrofluoric acid + 0.17 M potassium fluoride <em>is a good buffer system </em>because HF is a weak acid and KF (F⁻ in aqueous medium), is its conjugate base
0.20 M hydrobromic acid + 0.22 M sodium bromide <em>is not a good buffer system </em>because HBr is a strong acid.
The number of protons in an uncharged atom equals the number of electrons.
Answer:
Mass = 112 g
Explanation:
Given data:
Mass of CO₂ produced = 90.6 g
Mass of oxygen needed = ?
Solution:
Chemical equation:
C₃H₈ + 5O₂ → 3CO₂+ 4H₂O
Number of moles of CO₂:
Number of moles = 90.6 g/ 44 g/mol
Number of moles = 2.1 mol
Now we will compare the moles of CO₂ and oxygen:
CO₂ : O₂
3 : 5
2.1 : 5/3×2.1 = 3.5
Mass of oxygen needed:
Mass = number of moles × molar mass
Mass = 3.5 mol × 32 g/mol
Mass = 112 g
Mix aloe vera and honey or olive oil if you want. the internet says yogurt but thats disgusting so dont do that but if you wanna do that then thats fine go for it.
Answer:
warm, dry downslope wind affecting Southern California - Santa Ana wind
a seasonally changing wind- monsoon
wind blowing from a valley up a mountain slope - valley breeze
generated by cold thunderstorm downdrafts - haboob
Explanation:
The Santa Ana wind occurs in early autumn. They bring hot and dry weather to areas around the South-West coast. They move at high speeds, affecting most parts of Southern California.
Monsoon is a seasonal wind that blows across Southern Asia. It usually blows in summer. It is a a seasonally changing wind.
Valley breeze is an example of convection current in nature. It is produced by rapid warming of the valley floor leading to the expansion of air making it to flow up the slopes. At night, radiation from the surface cools the slopes. This leads to the rise of cooler and denser air which drains into the valley.
Haboob is generated by cold thunderstorm downdrafts. It is associated with large sandstorms and dust storms.