1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
devlian [24]
3 years ago
13

Please help me with these I'll give 15 points

Chemistry
2 answers:
VLD [36.1K]3 years ago
5 0
1.d
2.g
3.j
4.i
5.c
6.h
7.e
8.b
9.a
10.f
sveticcg [70]3 years ago
4 0
1) D
2) G
3) J
4) I
5) C
6) H
7) E
9) A
10) F
You might be interested in
A white coloured solid salt “A” on heating gives out two colourless gases “B” and “C”.
QveST [7]
I think it say go rggdggy and do something with one of those other things and get a work order and get the t off and u I know I have
6 0
3 years ago
Potassium-40 is a radioactive isotope that decays into a single argon-40 atom and other particles with a half-life of 1:25 billi
stiks02 [169]

Answer:

0.147 billion years = 147.35 million 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 Potassium-40 is 1.25 billion 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/(1.25 billion years) = 0.8 billion year⁻¹.

  • Also, we have the integral law of first order reaction:

<em>kt = ln([A₀]/[A]),</em>

<em></em>

where, k is the rate constant of the reaction (k = 0.8 billion year⁻¹).

t is the time of the reaction (t = ??? year).

[A₀] is the initial concentration of (Potassium-40) ([A₀] = 100%).

[A] is the remaining concentration of (Potassium-40) ([A] = 88.88%).

  • At the time needed to be determined:

<em>8 times as many potassium-40 atoms as argon-40 atoms. Assume the argon-40 only comes from radioactive decay.</em>

  • If we start with 100% Potassium-40:

∴ The remaining concentration of Potassium-40 ([A] = 88.88%).

and that of argon-40 produced from potassium-40 decayed = 11.11%.

  • That the ratio of (remaining Potassium-40) to (argon-40 produced from potassium-40 decayed) is (8: 1).

∴ t = (1/k) ln([A₀]/[A]) = (1/0.8 billion year⁻¹) ln(100%/88.88%) = 0.147 billion years = 147.35 million years.

8 0
3 years ago
Find the mass of carbon in a sample of hcn with a mass of 3.37 g
dsp73

Answer:

我實際

Explanation:

我實際上不知道答案,我只是為了點數而這樣做,哈哈,祝你好運哈哈我實際上不知道答案,我只是為了點數而這樣做,哈哈,祝你好運哈哈我實際上不知道答案,我只是為了點數而這樣做,哈哈,祝你好運哈哈

7 0
3 years ago
At a wastewater treatment plant, FeCl3(s) is added to remove excess phosphate from the effluent. Assume the following reactions
RoseWind [281]

Answer : The concentration of Fe^{3+} needed is, 2.37\times 10^4M

Explanation :

First we have to calculate the mole of phosphate.

As we are given that, 1 mg P/L that means, 1 mg of phosphate present in 1 L of solution.

\text{Moles of phosphate}=\frac{\text{Mass of phosphate}}{\text{Molar mass of phosphate}}

Molar mass of phosphate = 94.97 g/mole

\text{Moles of phosphate}=\frac{1mg}{94.97g/mol}=\frac{0.001g}{94.97g/mol}=1.053\times 10^{-5}mol

Now we have to calculate the concentration of phosphate.

\text{Concentration of phosphate}=\frac{\text{Moles of phosphate}}{\text{Volume of solution}}

\text{Concentration of phosphate}=\frac{1.053\times 10^{-5}mol}{1L}=1.053\times 10^{-5}mol/L

Now we have to calculate the concentration of Fe^{3+}.

The second equilibrium reaction is,

FePO_4\rightleftharpoons Fe^{3+}+PO_4^{3-}

The solubility constant expression for this reaction is:

K_{sp}=[Fe^{3+}][PO_4^{3-}]

Given: K_{sp}=\frac{1}{4}

\frac{1}{4}=[Fe^{3+}]\times 1.053\times 10^{-5}mol/L

[Fe^{3+}]=2.37\times 10^4M

Thus, the concentration of Fe^{3+} needed is, 2.37\times 10^4M

8 0
4 years ago
How does hydrogen peroxide bleach hair?
harkovskaia [24]

How does hydrogen peroxide bleach hair? THe h202 molecule sbreak the double bonds in pigment molecules


Question 3

What advantage does hydrogen peroxide have over other bleaching agents such as chlorine gas? Hydrogen peroxide decomposes into nontoxic water and oxygen.  

Question 4

How does hydrogen peroxide play a role in air pollution?Peroxide fragments react with unburned fuel creating eye irritants.

Question 5

In the reaction between melanin and hydrogen peroxide, which substance is oxidized (receives electrons)? melanin is oxidized,hydrogen peroxide is reduced


8 0
4 years ago
Other questions:
  • Purpose of boiling chip
    10·1 answer
  • Determine the molarity of the solution assuming the salt water solution has a density of 1.01 g/cm3.
    11·1 answer
  • 3. What is the volume of 0.750 mol of argon at STP?​
    9·1 answer
  • A cube has a mass of 456 g and a volume of 13 c. What is the density?
    6·1 answer
  • When do we classify a disease as epidemic
    14·2 answers
  • What do you notice with your answer​
    12·1 answer
  • Is glucose a element or compound
    9·2 answers
  • How important is economic in your everyday life
    14·1 answer
  • 71. The density of osmium (the densest metal) is 22.57 g/cm². If a
    14·1 answer
  • Help me with this plz
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!