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
wlad13 [49]
3 years ago
15

If the half life is 6.3 minutes how much of a 128.0 milligram sample will remain after 15 minutes​

Chemistry
1 answer:
zaharov [31]3 years ago
6 0

Answer:

24.5

Explanation:

15/6.3 => 2.38 half lives passed.

.5^2.38 => 0.19198 decimal representation of the percentage that is left over after 2.38 half lives have passed.

0.19198 *128 = 24.5 mg of the material remaining.

You might be interested in
(6 points) Calculate the maximum number of moles and grams of H2S that can form when 158 g of aluminum sulfide reacts with 131 g
Schach [20]

Answer:107.1 g, 124.1 g

Explanation:

The equation of the reaction is;

Al2S3(s) + 6H20(l) ----> 2Al(OH)3(s) + 3H2S(g)

Hence;

For Al2S3

Number of moles= reacting mass/molar mass

Number of moles = 158g/150gmol-1 =1.05 moles

If 1 mole of Al2S3 yields 3 moles of H2S

1.05 moles of Al2S will yield

1.05 × 3/1 = 3.15 moles

Mass of H2S = 3.15moles × 34 gmol-1 = 107.1 g

For water

Number of moles of water = 131g/18gmol-1= 7.3 moles

6 moles of water yields 3 moles of H2S

7.3 moles of water will yield 7.3 × 3/6 = 3.65 moles of H2S

3.65 moles × 34 gmol-1 =124.1 g

5 0
3 years ago
Why carbon dioxide is much more soluble in alkaline solutions​
rewona [7]

Answer:

<em>Because CO2 dissolved in water is acidic: it forms carbonic acid. The second equilibrium below strongly favors dissolved CO2</em>

<em>Hope</em><em> </em><em>it</em><em> </em><em>will</em><em> </em><em>help</em><em> </em><em>you</em>

3 0
3 years ago
Read 2 more answers
When the coffee is brewed according to directions, a pound of coffee beans yields 50 cups of coffee (4 cups = 1 qt). How many kg
Xelga [282]

1 pound of coffee is said to yield 50 cups of coffee

So we need to find the pounds of coffee beans required to produce 250 cups

so if 50 cups need 1 pound of coffee beans

therefore 250 cups need - 1/50 x 250 = 5 pounds of coffee beans

since we have to find the amount of coffee beans needed in kg, we have to convert pounds to kg

1 pound = 0.45 kg

So if 1 pound is equivalent to 0.45 kg

then 5 pounds are equivalent to - 0.45 kg/pound x 5 pounds = 2.25 kg

therefore 2.25 kg of coffee beans are required

4 0
3 years ago
Read 2 more answers
An electric kettle draws a current of 6.50 A while it is plugged into a 120-V
Umnica [9.8K]

Answer:

780 watts

Explanation:

formula to find power when given amps and voltage

P = A x V

=6.50a x 120V

= 780 W (watts)

7 0
3 years ago
Based on the balanced chemical equation for the preparation of malachite, what is the composition of the bubbles formed when sod
spin [16.1K]

Answer:

Carbon Dioxide = CO2

Explanation:

The synthesis of Malachite is seen in the chemical formula:

CuSO 4 . 5H2O(aq) + 2NaCO3(aq) --> CuCO 3 Cu(OH) 2 (s) + 2Na 2 SO 4 (aq) + CO 2 (g) + 9H 2 O(l)

The bubbles mentioned in the question hints that our interest is the compounds in their gseous phase  (g).

Upon examining the chemical equation, only CO2 is in the gaseous state and hence the only one that can be formed as bubbles,

3 0
3 years ago
Other questions:
  • What is the volume of an irregular object if the initial volume in the graduated cylinder is 3.50 ml and it rises to 7.50 ml aft
    15·1 answer
  • Which is more soluble at 28
    9·2 answers
  • Which option is an example of a chemical property? Question options: reactivity color melting point density
    15·2 answers
  • Practice Problem 07.61 Draw the major product that is obtained when (2S,3S)-2-Bromo-3-phenylbutane is treated with sodium ethoxi
    10·1 answer
  • How many molecules of NH3 are produced from 8.01x10-4g of H2
    9·1 answer
  • Volume is the quantity of two-dimensional space occupied by a liquid, solid, or gas.
    5·2 answers
  • In the following neutralization reaction, which substance is the acid?
    13·2 answers
  • Determine the number of valence electrons for the following: [kr] 5s2 4d6
    5·1 answer
  • Do oxygen atoms become more stable or less stable when oxygen forms compounds? Explain. Pls help
    10·1 answer
  • ____ occurs when the vapor pressure of a liquid is equal to the external atmospheric pressure.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!