Cane sugar is being manufactured at the rate of 500 kg/hr from sugar canes that have the following composition (% by weight):

A sample contains 25% parent isotope and 75% daughter isotopes. If the half-life of the parent isotope is 72 years, how old is t

alisha [4.7K]

The radioactive decay obeys first order kinetics

the rate law expression for radioactive decay is

$ln\frac{[A_{0}]}{[A_{t}]}=kt$

Where

A0 = initial concentration

At = concentration after time "t"

t = time

k = rate constant

For first order reaction the relation between rate constant and half life is:

$k=\frac{0.693}{t_{\frac{1}{2} } }$

Let us calculate k

k = 0.693 / 72 = 0.009625 years⁻¹

Given

At = 0.25 A0

$ln(\frac{A0}{0.25A0})=0.009625 X time$

time = 144 years

So after 144 years the sample contains 25% parent isotope and 75% daughter isotopes**

Simply two half lives

5 0

3 years ago

Read 2 more answers

Pls help Would be much appreciated:)

Pie

Answer:

Ok so, b. A redox reaction occurs in an electrochemical cell, where silver (Ag) is oxidized and nickel (Ni) is reduced - In voltaic cells, also called galvanic cells, oxidation occurs at the anode and reduction occurs at the cathode. A mnemonic for this is "An Ox. Red Cat." So since silver is oxidized, the silver half-cell is the anode. And the nickel half-cell is the cathode...

i. Write the half-reactions for this reaction, indicating the oxidation half-reaction and the reduction half-reaction- The substance having highest positive potential will always get reduced and will undergo reduction reaction. Here, zinc will always undergo reduction reaction will get reduced

ii. Which metal is the anode, and which is the cathode?-The anode is where the oxidation reaction takes place. In other words, this is where the metal loses electrons. The cathode is where the reduction reaction takes place.

iii. Calculate the standard potential (voltage) of the cell

Look up the reduction potential,

E

⁰

red

, for the reduction half-reaction in a table of reduction potentials

Look up the reduction potential for the reverse of the oxidation half-reaction and reverse the sign to obtain the oxidation potential. For the oxidation half-reaction,

E

⁰

ox

=

-

E

⁰

red

.

iv. What kind of electrochemical cell is this? Explain your answer.

All parts in the electrochemical cells are labeled in second figure. Following are the part in electrochemical cells

1) Anode 2) Cathode 3) gold Stripe (Electrode) 4) Aluminium Glasses (Electrode) 5) Connecting wires 6) Battery

Explanation:

3 0

2 years ago

58. A cylinder of a gas mixture used for calibration of blood gas analyzers in medical laboratories contains 5.0% CO2, 12.0% O2,

erica [24]

Answer and Explanation:

$Greetings!$

$Let's~answer~your~question!$

$Partial ~pressure ~of ~gas ~can ~be ~directly~ calculated ~by ~multiplying ~the~ percentage\\ of~ pressure~ of~ gases~ to ~the ~total ~pressure.$

$\boxed{Pgas~ = ~P~total~ * \% ~P ~of ~gas}$

For % of N2 gas: 

 $100\% - (5\% + 12\%) = 83\% ~N2$ 

 $PN_2 ~= ~146~ atm~ *~ 0.83 ~ = 121.18 ~atm$ 

 $PO_2 ~= ~146~ atm~ *~ 0.12~ = 17.52 ~atm$ 

 $~PCO_2~ = ~146~ atm ~* 0.05 = 7.3 ~atm$ 

3 0

3 years ago

9.05 mol of oxygen gas to g of oxygen gas

NARA [144]

Molar mass of oxygen gas:

O₂ = 16 * 2 = 32.0 g/mol

1 mole O₂ -------------- 32.0
9.05 mole O₂ ---------- ?

Mass = 9.05 * 32.0

Mass = 289.6 g of O₂

hope this helps!

7 0

2 years ago

Suppose 110.0 mL110.0 mL of hydrogen gas at STP combines with a stoichiometric amount of fluorine gas and the resulting hydrogen

Fittoniya [83]

Suppose 110.0 mL of hydrogen gas at STP combines with a stoichiometric amount of fluorine gas and the resulting hydrogen fluoride dissolves in water to form 150.0 mL of an aqueous solution. 0.032 M is the concentration of the resulting hydrofluoric acid.

<h3>What is Balanced Chemical Equation ?</h3>

The balanced chemical equation is the equation in which the number of atoms on the reactant side is equal to the number of atoms on the product side in an equation.

Now write the balanced chemical equation

H₂ + F₂ → 2HF

<h3>What is Ideal Gas ?</h3>

An ideal gas is a gas that obey gas laws at all temperature and pressure conditions. It have velocity and mass but do not have volume. Ideal gas is also called perfect gas. Ideal gas is a hypothetical gas.

It is expressed as:

PV = nRT

where,

P = Pressure

V = Volume

n = number of moles

R = Ideal gas constant

T = temperature

Here,

P = 1 atm [At STP]

V = 110 ml = 0.11 L

T = 273 K [At STP]

R = 0.0821 [Ideal gas constant]

Now put the values in above expression

PV = nRT

1 atm × 0.11 L = n × 0.0821 L.atm/ K. mol × 273 K

$n = \frac{1\ \text{atm} \times 0.11\ L}{0.0821\ \text{L. atm/ K. mol} \times 273\ K}$

n = 0.0049 mol

<h3>How to find the concentration of resulting solution ? </h3>

To calculate the concentration of resulting solution use the expression

$C = \frac{n}{V}$

$= \frac{0.0049}{0.15}$

= 0.032 M

Thus from the above conclusion we can say that Suppose 110.0 mL of hydrogen gas at STP combines with a stoichiometric amount of fluorine gas and the resulting hydrogen fluoride dissolves in water to form 150.0 mL of an aqueous solution. 0.032 M is the concentration of the resulting hydrofluoric acid.

Learn more about the Ideal Gas here: brainly.com/question/25290815
#SPJ4

4 0

2 years ago