Answer:
47.9 g of ethanol
Explanation:
Combustion is a chemical reaction in which a substance reacts with oxygen to produce heat and light. Combustion reactions have been very useful as a source of energy. Ethanol is now burnt for energy purposes as a fuel. Ethanol has even been proposed as a possible alternative to fossil fuels.
Since 1 mole of ethanol when combusted releases 1367 kJ/mol of energy
x moles of ethanol releases 1418 kJ/mol.
x= 1 × 1418 kJ/mol/ 1367 kJ/mol
x= 1.04 moles of ethanol.
Mass of ethanol = number of moles × molar mass
Molar mass of ethanol = 46.07 g/mol
Mass of ethanol = 1.04 moles × 46.07 g/mol
Mass of ethanol= 47.9 g of ethanol
Explanation:
A strip of solid palladium metal is put into a beaker of nicl2
Palladium (Pd) + Nickel Chloride (NiCl2)
To answer this question properly you must refer to the reactivity series.
The activity series is a chart of metals listed in order of declining relative reactivity. The top metals are more reactive than the metals on the bottom.
In this series, Nickel is higher than Palladium. This means that if a Palladium strip is placed into a solution of a Ni salt, then a reaction will not take place, nothing would happen.
Because Pd is lower than Ni in the reactivity series.
There is no reaction so no equation.
Answer:
5.0 x 10⁹ years.
Explanation:
- It is known that the decay of a radioactive isotope isotope obeys first order kinetics.
- Half-life time is the time needed for the reactants to be in its half concentration.
- If reactant has initial concentration [A₀], after half-life time its concentration will be ([A₀]/2).
- Also, it is clear that in first order decay the half-life time is independent of the initial concentration.
- The half-life of K-40 = 1.251 × 10⁹ years.
- For, first order reactions:
<em>k = ln(2)/(t1/2) = 0.693/(t1/2).</em>
Where, k is the rate constant of the reaction.
t1/2 is the half-life of the reaction.
∴ k =0.693/(t1/2) = 0.693/(1.251 × 10⁹ years) = 5.54 x 10⁻¹⁰ year⁻¹.
- Also, we have the integral law of first order reaction:
<em>kt = ln([A₀]/[A]),</em>
where, k is the rate constant of the reaction (k = 5.54 x 10⁻¹⁰ year⁻¹).
t is the time of the reaction (t = ??? year).
[A₀] is the initial concentration of (K-40) ([A₀] = 100%).
[A] is the remaining concentration of (K-40) ([A] = 6.25%).
∴ (5.54 x 10⁻¹⁰ year⁻¹)(t) = ln((100%)/( 6.25%))
∴ (5.54 x 10⁻¹⁰ year⁻¹)(t) = 2.77.
∴ t = 2.77/(5.54 x 10⁻¹⁰ year⁻¹) = 5.0 x 10⁹ years.
Answer:
ScCl₂
General Formulas and Concepts:
<u>Chemistry</u>
- Reading a Periodic Table
- Reaction Prediction
- Determining Chemical Compounds
Explanation:
<u>Step 1: Define</u>
Scandium (II)
Cl
<u>Step 2: Determine Charges</u>
Sc²⁺
Cl⁻
<u>Step 3: Predict Compound</u>
<em>We need to balance out the charges so the overall charge is 0.</em>
ScCl₂
<u>Step 4: Reaction</u>
RxN: Sc²⁺ + Cl₂ → ScCl₂