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
Reptile [31]
3 years ago
10

scandium47 has a half-life of 35s. suppose you have a 45g sample of scadium 47 how much of the sample remains unchanged after 14

0 seconds
Chemistry
1 answer:
Mars2501 [29]3 years ago
4 0

 The much  of the sample that would remain  unchanged  after 140 seconds is 2.813 g

Explanation

Half life  is time taken for the quantity  to reduce  to half its original value.

if the half life  for Scandium  is 35 sec, then the number  of half life in 140 seconds

=140 sec/ 35 s = 4 half life

Therefore 45 g after first half life = 45 x1/2 =22.5 g

               22.5 g after second half life = 22.5 x 1/2 =11.25 g

            11.25 g after third half life = 11.25 x 1/2 = 5.625 g

             5.625 after  fourth half life = 5.625 x 1/2 = 2.813

therefore 2.813 g  of Scandium 47 remains  unchanged.

You might be interested in
A 20.0–milliliter sample of 0.200–molar K2CO3 so­lution is added to 30.0 milliliters of 0.400–mo­lar Ba(NO3)2 solution. Barium c
iragen [17]

Answer:

[Ba^2+] = 0.160 M

Explanation:

First, let's calculate the moles of each reactant with the following expression:

n = M * V

moles of K2CO3 = 0.02 x 0.200 = 0.004 moles

moles of Ba(NO3)2 = 0.03 x 0.400 = 0.012 moles

Now, let's write the equation that it's taking place. If it's neccesary, we will balance that.

Ba(NO3)2 + K2CO3 --> BaCO3 + 2KNO3

As you can see, 0.04 moles of  K2CO3 will react with only 0.004 moles of Ba(NO3) because is the limiting reactant. Therefore, you'll have a remanent of

0.012 - 0.004 = 0.008 moles of Ba(NO3)2

These moles are in total volume of 50 mL (30 + 20 = 50)

So finally, the concentration of Ba in solution will be:

[Ba] = 0.008 / 0.050 = 0.160 M

6 0
3 years ago
Figure 2 shows what happens to the electrons in the outer shells when a sodium atom reacts with a fluorine atom.
QveST [7]

Sodium reacts with fluorine to make a covalent bond between them.  A covalent bond is formed when there is a mutual sharing of electrons between the two adjacent atoms.

Here, Sodium is metal and fluorine is non-metal. So, the bond between them may be an ionic bond, but as the Sodium has one valence electron and fluorine is highly electronegative. Sodium wants to lose electrons and fluorine wants to gain electrons to form a chemical bond. Therefore, the sodium donates its valence electron to fluorine, forms a cation, and fluorine accepts the electron and forms an anion and they distribute the difference in the charge between them.

So, we can say that when sodium and fluorine react to form sodium fluoride with a covalent bond.

Learn more about covalent bonds here:

brainly.com/question/12732708

#SPJ10

4 0
2 years ago
Neutral atoms of a specific element can have different numbers of which of the following?
Anit [1.1K]
Neutrons for example isotopes
8 0
3 years ago
20 POINTS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Amanda [17]
The KE can be solve using the formula:
ke = 0.5 mv^2
where m is the mass of the object
v is the velocity
ke = 0.5 ( 2 kg ) ( 5 m/s)^2
ke = 25 J

the GPE can be solved using the formula:
GPE = mgh
where m is the mass
g is the acceleration due to gravity ( 9.81 m/s^2)
h is the height

GPE = ( 4 kg)(9.81 m/s^2)( 40 m)
GPE = 392.4 J
4 0
3 years ago
AgBr+Cl2=AgCl+Br2 <br><br><br> REDOX!! HELP PLZ A LOT OF POINTS
mars1129 [50]

2AgBr+Cl2=2AgCl+Br2

You want everything to be the same on both sides the easiest way to do that is draw a line down the equal sign and write out all you compound and how many there are and do the same on the other side until there even

4 0
3 years ago
Other questions:
  • jin has four colorful glass bottles on his windowsill. one is red, one is violet, one is green, and one is yellow. the light tha
    8·2 answers
  • If the weight of an object is greater than the buoyant force acting on it, it will sink. What is the weight of a block of iron w
    6·2 answers
  • What is the electron configuration of ClS2?
    11·1 answer
  • Match the correct definition with the correct term from questions 10-13: A. Internal energy B. Latent heat C. Chemical (bond) en
    14·1 answer
  • What volume (in mL) of a 0.150 M HNO 3 solution will completely react with 35.7 mL of a 0.108 M Na 2 CO 3 solution according to
    14·1 answer
  • C Give two reasons why the formation of aluminium by electrolysis is very<br> expensive:
    8·1 answer
  • 1. How many grams are in 1.4 moles of Mg(NO3)2?
    10·1 answer
  • Which statement best describes the message of the poem? *
    5·2 answers
  • How many moles of RbNO2 are present in a sample with 3.4 x 1024 particles?
    11·1 answer
  • Which comppund contains both ionic and covalent bonds
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!