Potassium oxide is an ionic compound. The potassium has a charge of <span>K+</span> and oxygen has a charge of <span>O<span>2−</span></span>. We need 2 potassium ions to balance one oxide ion making the formula <span><span>K2</span>O</span>.
Potassium hydroxide is an ionic compound. The potassium has a charge of <span>K+</span> and hydroxide has a charge of <span>OH−</span>. We need 1 potassium ion to balance one hydroxide ion making the formula KOH.
<span><span>K2</span>O+<span> H2</span>O→KOH</span>
To balance the equation we place a coefficient of 2 in front of the potassium hydroxide.
<span><span>K2</span>O+<span>H2</span>O→2KOH</span>
I hope this was helpful.
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.
pH of the acetyl choline solution before incubation = 7.65
pH of the solution after incubation = 6.87
The difference in concentration of hydronium ion before and after incubation
=-=
This difference in hydronium ion concentration can be attributed to the increase in the concentration of acetic acid, which is formed when acetylcholine is hydrolyzed by acetycholinesterase. The mole ratio of acetylcholine to acetic acid is 1:1.
Therefore the moles of acetylcholine =
Answer:GLACIERS ARE MADE UP OF FALLEN SNOW OVER MILLION YEARS, IN MOST OF POLAR REGIONS IT TURNS TO ICE AND WILL FLOW DOWNWARDS AND OUTWARDS UNDER ITS OWN PRESSURE
AND THE LARGEST GLACIER IN THE WORLD IS 60 MILES WIDE AND AROUND 270 MILES LONG.
IT COVERS 10% OF EARTH'S TOTAL LAND
Explanation:
A. We can calculate the initial concentrations of each by
the formula:
initial concentration ci = initial volume * initial
concentration / total mixture volume
where,
total mixture volume = 10 mL + 20 mL + 10 mL + 10 mL = 50
mL
ci (acetone) = 10 mL * 4.0 M / 50 mL = 0.8 M
ci (H+) = 20 mL * 1.0 M / 50 mL = 0.4 M (note: there is only 1 H+ per
1 HCl)
ci (I2) = 10 mL * 0.0050 M / 50 mL = 0.001 M
B. The rate of reaction is determined to be complete when
all of I2 is consumed. This is signified by complete disappearance of I2 color
in the solution. The rate therefore is:
rate of reaction = 0.001 M / 120 seconds
rate of reaction = 8.33 x 10^-6 M / s