Answer:
E = 0.062 V
Explanation:
(a) See the attached file for the answer
(b)
Calculating the voltage (E) using the formula;
E = - (2.303RT/nf)log Cathode/Anode
Where,
R = 8.314 J/K/mol
T = 35°C = 308 K
F- Faraday's constant = 96500 C/mol,
n = number of moles of electron = 2
Substituting, we have
E = -(2.303 * 8.314 *308/2*96500) *log (0.03/3)
= -0.031 * -2
= 0.062V
Therefore, the voltmeter will show a voltage of 0.062 V
Answer:
52.2 g
Explanation:
Step 1: Write the balanced equation
3 KOH + H₃PO₄ ⟶ K₃PO₄ + 3 H₂O
Step 2: Calculate the moles corresponding to 89.7 g of KOH
The molar mass of KOH is 56.11 g/mol.
89.7 g × 1 mol/56.11 g = 1.60 mol
Step 3: Calculate the moles of H₃PO₄ needed to react with 1.60 moles of KOH
The molar ratio of KOH to H₃PO₄ is 3:1. The moles of H₃PO₄ needed are 1/3 × 1.60 mol = 0.533 mol.
Step 4: Calculate the mass corresponding to 0.533 moles of H₃PO₄
The molar mass of H₃PO₄ is 97.99 g/mol.
0.533 mol × 97.99 g/mol = 52.2 g
Answer: x=41
Sin, cos and tan are part of the trigonometric function. Sin is calculated from opposite/hypotenuse, while cos is calculated from adjacent/hypotenuse.
There is some formula that can be derived from the equation. One of them is sin (90-x)= cos x
If you use it, the calculation would be:
<span>sin 49° = cos x
</span><span>sin 49= sin (90-x)
49= 90-x
x= 90-49= 41</span>
The wavelength is obtained as 122 nm. Option A
<h3>What is the wavelength?</h3>
We know that from the Bohr model of the atom, an electron can move from a higher energy level to a lower energy level or from a lower energy level to a higher energy level. This is the idea of energy quantization as put forward by Neill Bohr.
The wavelength can be obtained by the use of the formula;
1/λ = RH(1/n^2initial - 1/n^2 final)
λ = wavelength of the emitted light
RH = Rydberg's constant
n intial = initial energy level
nfinal = final energy level
Thus;
1/λ = 1.09 * 10^7(1/1^2 - 1/2^2)
1/λ = 1.09 * 10^7( 1 - 0.25)
λ = 122 nm
Learn more about the wavelength:brainly.com/question/13533093
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Accuracy is the closeness of a measurement to the true value. Precision is the closeness of agreement among a set of results.
Suppose you read a refrigerator thermometer five times and get the Celsius readings 39.0, 39.3, 39.0, 39.1, and 39.0.
The average temperature is 39.1 °C. Your readings are <em>precise</em> because most of the readings are within 0.1 °C of the average.
However, if the actual refrigerator is 37.0 °C, your readings are <em>not accurate</em> because they are off by about 2°C.
If you use a thermocouple and get an average reading of 37.00, 37.03, 37.00, 37.01,and 37.00, your readings are both <em>accurate</em> and <em>more precise</em> than those from the refrigerator thermometer.
