This question is missing the part that actually asks the question. The questions that are asked are as follows:
(a) How much of a 1.00 mg sample of americium remains after 4 day? Express your answer using 2 significant figures.
(b) How much of a 1.00 mg sample of iodine remains after 4 days? Express your answer using 3 significant figures.
We can use the equation for a first order rate law to find the amount of material remaining after 4 days:
[A] = [A]₀e^(-kt)
[A]₀ = initial amount
k = rate constant
t = time
[A] = amount of material at time, t.
(a) For americium we begin with 1.00 mg of sample and must convert time to units of years, as our rate constant, k, is in units of yr⁻¹.
4 days x 1 year/365 days = 0.0110
A = (1.00)e^((-1.6x10^-3)(0.0110))
A = 1.0 mg
The decay of americium is so slow that no noticeable change occurs over 4 days.
(b) We can simply plug in the information of iodine-125 and solve for A:
A = (1.00)e^(-0.011 x 4)
A = 0.957 mg
Iodine-125 decays at a much faster rate than americium and after 4 days there will be a significant loss of mass.
Answer:
NaCl + AgF → NaF + AgCl
Explanation:
A double replacement reaction is a type of chemical reaction that occurs when two reactants exchange cations or anions to yield two new products.
From all the reactions given ,
- 2Na + Cl₂ → 2NaCl is an example of combination reaction because two or more reactants (Na & Cl₂) react with each other to form a single product (NaCl)
- H₂SO₃ → H₂O + SO₂ is an example of decomposition reaction because a single reactant (H₂SO₃) breaks down into two or more products (H₂O & SO₂).
- 2K + 2H₂O → 2KOH + H₂ is an example of displacement reaction because a highly reactive element (K) displaces a least reactive element (H) from its compound (H₂O).
- NaCl + AgF → NaF + AgCl is an example of double replacement reaction because there's an exchange between Cations (
&
) and Anions (
&
).
Answer:
a.
Turn paper Blue - these are alkaline/ base substances.
Turn paper Red - these substances are acidic in nature.
- Lemon Juice
- Vinegar
- Cola drink
b. i. A wasp sting - Lemon juice
ii. A bee sting - Toothpaste
iii. A wasp sting is alkaline which means that running an acidic substance like lemon or lemon juice on it should neutralize it.
A bee sting is acidic so an alkaline substance such as toothpaste should neutralize it as well.
Answer:
the velocity is 25 m/s
Explanation:
The computation of the velocity is shown below:
As we know that
Magnitude of Momentum = (mass) × (speed)
75 kg. m/s = 3 kg × speed
So, the speed is
= 75 ÷ 3
= 25 m/s
hence, the velocity is 25 m/s