Answer:
A. C₃H₄N
Explanation:
- Firstly, we need to calculate the no. of moles of C, H, and N using the relation:
<em>no. of moles = mass/molar mass.</em>
<em></em>
∴ no. of moles of C = mass/molar mass = (90.0 g)/(12.0 g/mol) = 7.5 mol.
∴ no. of moles of H = mass/molar mass = (11.0 g)/(1.0 g/mol) = 11.0 mol.
∴ no. of moles of N = mass/molar mass = (35.0 g)/(14.0 g/mol) = 2.5 mol.
- We should get the mole ratio of each atom by dividing by the lowest no. of moles (2.5 mol of N).
∴ the mole ratio of C: H: N = (7.5 mol/2.5 mol): (11.0 mol/2.5 mol): (2.5 mol/2.5 mol) = (3: 4.4: 1) ≅ (3: 4: 1).
- So, the empirical formula is: A. C₃H₄N.
<u>Answer:</u> The initial amount of Uranium-232 present is 11.3 grams.
<u>Explanation:</u>
All the radioactive reactions follows first order kinetics.
The equation used to calculate half life for first order kinetics:
We are given:
Putting values in above equation, we get:
Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = 206.7 yrs
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount of the reactant = ?
[A] = amount left after decay process = 1.40 g
Putting values in above equation, we get:
![0.0101yr^{-1}=\frac{2.303}{206.7yrs}\log\frac{[A_o]}{1.40}](https://tex.z-dn.net/?f=0.0101yr%5E%7B-1%7D%3D%5Cfrac%7B2.303%7D%7B206.7yrs%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B1.40%7D)
![[A_o]=11.3g](https://tex.z-dn.net/?f=%5BA_o%5D%3D11.3g)
Hence, the initial amount of Uranium-232 present is 11.3 grams.
Answer:
D
Explanation:
The specific heat capacity is the heat required to raise the temperature of 1kg of a substance by 1oC. Molar heat capacity of a substance is the heat requiredto raise the temperature of 1mole of a substance by 1oC. Molar heat capacity and specific heat capacity both decreases with increase in atomic weight. Increase in atomic weight also means increase in density of the substance.
Answer:
0.190 M
Explanation:
Let's consider the neutralization reaction between HCl and NaOH.
HCl + NaOH = NaCl + H2O
11.9 mL of 0.160 M NaOH were used. The reacting moles of NaOH were:
0.0119 L × 0.160 mol/L = 1.90 × 10⁻³ mol
The molar ratio of HCl to NaOH is 1:1. The reacting moles of HCl are 1.90 × 10⁻³ moles.
1.90 × 10⁻³ moles of HCl are in 10.0 mL of solution. The molarity of HCl is:
M = 1.90 × 10⁻³ mol / 10.0 × 10⁻³ L = 0.190 M
14.5 % carb
5.7% sugar
5.1% fiber
5.4% protein
0.4% fat
