Answer:
Group B is the control group
Explanation:
In an experiment, a control group is the standard to which comparisons are made in an experiment.
Answer:
Acetone
Explanation:
Chromatography has to do with the separation of substances by eluting the components of the solute using a mobile phase. The composition of the mixture to be separated decides the mixture of solvents (mobile phase) that are to be used for elution.
In this case the mixture to be separated comprises of substance A which is polar and substance B which is non polar. It is observed that the mobile phase moves B up the plate but not the polar substance, A. This means that a polar solvent such as acetone should be added to the mobile phase in order to achieve better elution of A.
The answer is: 8.14·10⁶³ moles of lithium are present.
N(Li₂SO₄) = 2.45·10⁸⁷; number of formula units of lithium sulfate.
n(Li₂SO₄) = N(Li₂SO₄) ÷ Na.
n(Li₂SO₄) = 2.45·10⁸⁷ ÷ 6.022·10²³ 1/mol.
n(Li₂SO₄) = 4.07·10⁶³ mol; amount of lithium sulfate
In one molecule of lithium sulfate, there are two atoms of lithium.
n(Li₂SO₄) : n(Li) = 1 : 2.
n(Li) = 2 · 4.07·10⁶³ mol.
n(Li) = 8.14·10⁶³ mol; amount of lithium atoms.
The non-contact forces portfolio includes Gravitational force, Magnetic force and Electrostatic force.
<h3>What is non contact force?</h3>
Non contact forces are those forces which are applied on any object without any physical interference or contact.
Some non-contact forces are:
- Gravitational force: It acts between two objects and depends on the masses of the object and distance between that objects.
- Magnetic force: It acts due to the motion of the charged particles.
- Electrostatic force: It is a type of induced force which is generated due to rubbing of two objects but when it is generated it remains even after removing the contact of previous objects.
Hence Gravitational force, Magnetic force and Electrostatic force are the non-contact forces.
To know more about non contact forces, visit the below link:
brainly.com/question/18451249
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Answer:
0.805 or 0.781 depending on the method used.
Explanation:
<u>Data</u><u> </u><u>provided</u>
half life ie t1/2= 8days.
No= 50g
t=48days
Nt=?
<u>Metho</u><u>d</u><u> </u><u>1</u>
<u>Formul</u><u>a</u><u>:</u><u> </u><u>N</u><u>t=</u><u> </u><u>No</u><u>(</u><u>1</u><u>/</u><u>2</u><u>)</u><u>^</u><u>n</u>
where n= number of half lives.
= t/t1/2 = 48/8
=6.
thus Nt= 50(1/2)^6= 0.781
<u>Metho</u><u>d</u><u> </u><u>2</u>
<u>Formul</u><u>a</u><u>:</u><u> </u><u>Nt</u><u>=</u><u> </u><u>Noe^-</u><u>(</u><u>lambda</u><u>)</u><u>t</u>
where lambda= decay constant
= ln2/ t1/2= ln2/ 8 = 0.086.
thus Nt= 50e^-(0.086×48)= 0.805.
