answer.
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
stellarik [79]
2 years ago
12

A particular radioactive isotope has a half-life of (2.50+a) hours. if you have (24.5+b) g of the isotope at 10:00 am, how much

will you have at 7:30pm? give your answer in grams (g)and with 3 significant figures.
Chemistry
1 answer:
gavmur [86]2 years ago
3 0
Its a not b and i dont know the reast

You might be interested in
Suppose you need 7.0 m of Grade 70 tow chain, which has a diameter of 38" and weighs , 2.16/kgm to tow a car. How would you calc
STatiana [176]

Answer : The mass of 7.0 m chain is, 15.12 kg

Explanation :

As we are given that,

The weight of the chain per unit length = 2.16 kg/m

Now we have to determine the mass of chain for 7.0 m length.

As, the mass of 1 m length of chain = 2.16 kg

So, the mass of 7.0 m length of chain = \frac{7.0m}{1m}\times 2.16kg

                                                                = 15.12 kg

Therefore, the mass of 7.0 m chain is, 15.12 kg

3 0
2 years ago
3. In what grade level do students grow the quickest?
Vadim26 [7]

Answer:

Independent Variable: Grade Level

Dependent Variable: Growth in height

Hypothesis: Students in [Insert the grade level you believe will grow the quickest here] will experience the quickest growth in height.

Explanation:

Independent variables are the factors in which you manipulate to gain your results, in this case you would be changing the grade level you would observe to see the height.

Dependent variables are the factors that respond to changes in the independent variables. You don't control these events, you simply observe them. In this case, you merely observe the growth in height in accordance to the different grade levels you observe.

For the hypothesis, you would create your own hypothesis based on a guess you have. You create a hypothesis not based on the data, but on what you believe will be correct before doing the experiment. It doesn't have to be the correct answer, but just your thoughts.

3 0
2 years ago
A sample of vinegar was found to have an acetic acid concentration of 0.8846 m. What is the acetic acid % by mass? Assume the de
jenyasd209 [6]

Answer:

5.3%

Explanation:

Let the volume be 1 L

volume , V = 1 L

use:

number of mol,

n = Molarity * Volume

= 0.8846*1

= 0.8846 mol

Molar mass of CH3COOH,

MM = 2*MM(C) + 4*MM(H) + 2*MM(O)

= 2*12.01 + 4*1.008 + 2*16.0

= 60.052 g/mol

use:

mass of CH3COOH,

m = number of mol * molar mass

= 0.8846 mol * 60.05 g/mol

= 53.12 g

volume of solution = 1 L = 1000 mL

density of solution = 1.00 g/mL

Use:

mass of solution = density * volume

= 1.00 g/mL * 1000 mL

= 1000 g

Now use:

mass % of acetic acid = mass of acetic acid * 100 / mass of solution

= 53.12 * 100 / 1000

= 5.312 %

≅ 5.3%

3 0
2 years ago
Three 5-l flasks, fixed with pressure gauges and small valves, each contains 4 g of gas at 273 k. flask a contains h2, flask b c
Varvara68 [4.7K]
First, please check the missing part in your question in the attachment.
a) So first, the Rank of pressure:
according to this formula PV = nRT and when n = m/Mw
PV = m/Mw * R*T
when we have the same mass m and the same V volume so P will proportional with the mole weight M as when the M is smaller the pressure will be greater 
when Mw of H2(A) = 2 g / Mw of He (B) = 4 g and Mw of CH4(C) = 16 g
∴ Pressure :
 (A) > (B) > (c)

B) The rank of average molecular kinetic energy:
when K = 3/2 KB T
when K is the average kinetic energy per molecule of gas 
and KB is Boltzmann's constant
and T is the temperature (K)
So from this equation, we can know that K only depends on T value, and when we have the T constant here for A, B, and C So the rank of K will be like the following:
∴ A = B = C
C) the rank of diffusion rate after the valve is opened:
according to this formula:
R2/R1 = √M1/M2
from this equation, we can see that diffusion is proportional to the reciprocal of the molecular mass M so,
when Mw H2 (A) = 2 g & Mw He(B) = 4 g & CH4 (C) = 16 g
∴ the rank of diffusion:
A > B > C

D) The rank of the Total kinetic energy of the molecules:
when we have the Mw different so it will make the no.of molecules differs as when the Mw is low the no.of molecules will be hight, and when the average molecular kinetic energy equals. so the total kinetic energy will depend on no. of molecules 
∵ Mw A < Mw B < Mw C 
∴no .of molecules of A > B >C
∴ the rank of total kinetic energy is:
A > B > C

e) the rank of density:

when ρ = m/ v 
and m is the mass & v is the volume and we have both is the same for A, B, and C
so the density also will be the same, ∴ the rank of the density is:
A = B = C

F) the rank of the collision frequency:
as the no.of molecules increase the collision frequency increase and depend also on the velocity and it's here the same.
∴ Collision frequency will only depend on the no.of molecules
we have no.of molecules of A > B > C as Mw A < B < C 
∴the rank of the collision frequency is:
A > B > C 

 



7 0
2 years ago
In the octapeptide ITPGAALY which amino acid is the amino-terminal residue? Tyrosine Leucine Proline Isoleucine
oee [108]

Answer:

The correct option is: Isoleucine

Explanation:

Peptides are the biological molecules containing amino acids which are linked together by peptide bonds. A polypeptide is a peptide chain in which more than 20 amino acids are linked together by peptide bond.

All polypeptide chains have a N-terminal and a C-terminal.

The N-terminal of a polypeptide is also known as the amino terminal. The N-terminal has a free amine group, which is generally on the left hand side of the polypeptide chain.

Therefore, the N-terminal or the amino terminal of the given polypeptide is Isoleucine (I).

5 0
2 years ago
Other questions:
  • What is the oxidation number for iodine in Mg(IO3)2 ?
    13·2 answers
  • There are two types of nucleic acids, dna and rna. nearly all organisms use dna, not rna, as the central repository for genetic
    15·1 answer
  • A compound composed of only c and f contains 17.39 c by mass. what is its empirical formula
    5·1 answer
  • F the solution described in the introduction is cooled to 0 ∘c, what mass of kno3 should crystallize?
    7·2 answers
  • There are ________ unpaired electrons in the Lewis symbol for a nitride ion.
    15·1 answer
  • Consider a process in which the entropy of a system increases by 125 J K−1 and the entropy of the surroundings decreases by 125
    13·1 answer
  • Why do the deprotonated organic acid (RCO2-) and protonated organic base (RNH3+) go into the aqueous layer?
    11·1 answer
  • This formula equation is unbalanced. P4(s) + Cl2(g) Right arrow. PCl3(l) Which coefficient should be placed in front of PCl3 to
    15·2 answers
  • 1. Carson completed conductivity testing on the solutions shown in the data table below and recorded his findings in the conduct
    6·1 answer
  • How many hydrogen molecules are there in 1 ton of hydrogen?​
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!