Answer:
<em>2.085 x 10^-20 J</em>
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Explanation:
minimum energy required to produce photoelectric effect in chromium is given as hf = 7.21 x 10^-19 J
The work function of chromium Ф = 4.37 eV = 7.00151 x 10^-19 J
The minimum energy required to eject an electron from from a chromium metal E = ?
From E = hf - Ф
substituting values, we have
E = (7.21 x 10^-19) - (7.00151 x 10^-19)
E = <em>2.085 x 10^-20 J</em>
Molar mass
Ca₃(PO₄)₂ = 310 g/mol
1 mole -------------------> 310 g
2.3x10⁻⁴ mole ---------> ?
m = 2.3x10⁻⁴ * 310 / 1
m = 0.0713 g
hope this helps!
Answer:
Mantle
Explanation:
Convection currents in the Earth occur in the mantle. The core of the Earth is extremely hot, and material in the mantle close to the core is heated...
Hope that help <3
Answer:
Explanation:
Since it first order, we use order rate equation
In (
) = -kt where A1 is the final quality = 0.8 (80%), A0 is the initial quality = 1 ( 100%)
also, t half life =
where k is rate constant
k =
= 0.0154
In (
) = - 0.0154 t
-0.223 / -0.0154 = t
t = 14.49 approx 14.5 days from the date the yogurt was packaged
Answer:
The answer is E. All of the statements describe the anomeric carbon.
Explanation:
When a sugar switches from its open form to its ring form, the carbon from the carbonyl (aldehyde if it is an aldose, or a ketone in the case of a ketose) suffers a nucleophilic addition by one of the hydroxyls in the chain, preferably one that will form a 5 or 6 membered ring after the reaction.
As such, the anomeric carbon will have two oxygens attached (The original one and the one that bonded when the ring closed).
It will be chiral, given that it has 4 different groups attached. (-OR,-OH,-H and -R, where R is the carbon chain).
The hydroxyl group can be in any position (Above of below the ring), depending on with side the addition took place. (See attachment)
It is the carbon of the carbonyl in the open-chain form of the sugar, because it is the only one that can react with the Hydroxyls.