What percentage of a substance remains after 7 half-lives have passed?

You were instructed to add 1.0 mL out of 4.0 mL of an undiluted sample to 99 mL of sterile diluent. Instead, you add the entire

finlep [7]

Answer:

A.) Intended dilution factor : 0.01

B.) Actual dilution factor: 0.039

Explanation:

Dilution factor(DF) is ratio of the volume of the undiluted sample to total volume of diluted solution

A.) What was your intended dilution factor

This would be the the addition 1.0ml from 4.0ml to 99ml of sterile

Volume of sterile diluent = 99ml

Volume of Undiluted sample = 1.0ml

Total volume of diluted solution = 99ml + 1m = 100ml

Dilution factor = Volume of undiluted sample ÷ Total volume of diluted solution

Dilution factor = 1:100

= 1ml ÷ 100ml

= 0.01

B.) What was your actual dilution factor?

This would be the entire addition of 4.0ml to 99ml sterile diluent

Volume of sterile diluent = 99ml

Volume of Undiluted sample = 4.0ml

Total volume of diluted solution = 99ml + 4.0ml = 103ml

Dilution factor = Volume of undiluted sample ÷ Total volume of diluted solution

Dilution factor

= 4:103

= 4ml ÷ 103ml

= 0.039

8 0

3 years ago

Energy conversions _____. can lose energy as sound can be 100 percent efficient if controlled properly are calculated by multipl

nikdorinn [45]

Answer:

are calculated by multiplying useful energy by the total amount of energy

Explanation:

The energy conversions are never 100 percent efficient. This is because the energy originally is converted into a mixture of the useful and not useful energy. For example, gasoline in the car is converted to motion, sound and friction. The later two (sound and friction) are energies but are less useful. Thus, in this case, the energy conversion is not 100 % efficient. Thus, the energy efficiency equation comes into play. This is given as the ratio of the useful energy to the total energy. It is a fraction.

6 0

4 years ago

Read 2 more answers

13.50 grams of Pb(NO3)4 are dissolved in enough water to make 250 mL of solution. What is the molar its of the resulting solutio

likoan [24]

Data:
M (molarity) = ? (M or Mol/L)
m (mass) = 13.50 g
V (volume) = 250 mL → 0.25 L
MM (Molar Mass) of Lead(IV) Nitrate $Pb(NO_3)_4$
Pb = 1*207 = 207 amu
N = (1*14)*4 = 14*4 = 56 amu
O = (3*16)*4 = 48*4 = 192 amu
------------------------------------
MM of $Pb(NO_3)_4$ = 207+56+192 = 455 g/mol

Formula:
$M = \frac{m}{MM*V}$

Solving:
$M = \frac{m}{MM*V}$
$M = \frac{13.50}{455*0.25}$
$M = \frac{13.50}{113.75}$
$M = 0.118681318...\:\:\to\:\:\boxed{\boxed{M \approx 0.119\:Mol/L}}\end{array}}\qquad\quad\checkmark$

Answer:
<span>B. 0.119 M</span>

5 0

4 years ago

According to VSEPR Theory, the molecular geometry for CH3+ is

Ne4ueva [31]

I think it’s C but anybody can correct me if I’m wrong

3 0

2 years ago

Give the spectator ions for the reaction that occurs when aqueous solutions of H 2SO 4 and KOH are mixed.

Sever21 [200]

Answer:

The spectator ions is: $K^+$ and $SO^{2-}_4$