Explanation:
Depression in Freezing point
= Kf × i × m
where m is molality , i is Van't Hoff factor, m = molality
Since molality and Kf remain the same
depression in freezing point is proportional to i
i= 2 for CuSO4 ( CuSO4----------> Cu+2 + SO4-2
i=1 for C2h6O
i= 3 for MgCl2 ( MgCl2--------> Mg+2+ 2Cl-)
So the freezing point depression is highest for MgCl2 and lowest for C2H6O
so freezing point of the solution = freezing point of pure solvent- freezing point depression
since MgCl2 has got highest freezing point depression it will have loweest freezing point and C2H6O will have highest freezing point
Answer:
the correct answer is 17 significant figures
Answer:
The pH is 7.54
Explanation:
The Henderson - Hasselbalch equation states that for a buffer solution which consists of a weak acid and its conjugate base, the buffer pH is given by:
pH ![=pk_{a} +log(\frac{[conjugate base]}{[weakacid]})](https://tex.z-dn.net/?f=%3Dpk_%7Ba%7D%20%2Blog%28%5Cfrac%7B%5Bconjugate%20base%5D%7D%7B%5Bweakacid%5D%7D%29)
pkₐ is for the acid
In this case, the buffer hypochlorous acid HClO is a weak acid, and its conjugate base is the hypochlorite anion ClO⁻ is delivered to the solution via sodium hypochlorite NaClO
.
NaCIO = 0.200 M
HCIO = 0.200 M
pkₐ = -log₁₀ kₐ = -log₁₀ (2.9 × 10⁻⁸) = 7.54
∴pH =
= 7.54
Answer: A lot of food chains
Explanation: A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community.
The correct answer is Three. Solving the given expression we get,
2.524 g (5.1 × 106 g) ÷ (6.85 × 103 g) = 1364.47÷ (6.85 × 103 g) = 1364.47÷ 705.55 = 1.93
Here, the number of significant figures is three. Thus, the result should have three <span>significant figures.</span>