Answer:
0.08 mL
Explanation:
The solution of the skin test has a concentration of 0.2% (w/v), which means that there are 0.2 g of the antigen per 100 mL of the solution. If a new solution will be done using it, then this solution will be diluted, and the mass of the antigen added must be the same in the volume taken and at the diluted solution.
The mass is the concentration (in g/mL) multiplied by the volume of the solution (in mL), so, if m is the mass, C the concentration, V the volume, 1 the initial solution, and 2 the diluted:
m1 = m2
C1*V1 = C2*V2
Where
C1 = 0.2 g/100 mL = 0.002 g/mL
V1 = ?
C2 = 0.04 mg/mL = 0.00004 g/mL
V2 = 4 mL
0.002*V1 = 0.00004*4
V1 = 0.08 mL
Answer:
A titration is a technique where a solution of known concentration is used to determine the concentration of an unknown solution. Typically, the titrant (the know solution) is added from a buret to a known quantity of the analyte until the reaction is complete
Answer : We can produce 125.7 g of 
.
Explanation : The reaction will be
The molecular mass of 
is 64.1 g/mol
and molecular mass of 
is 34.1 g/mol
For every mole of we would need twice of moles, so for every 3 moles of we need 16 moles of
Now, we can calculate number of moles
2.61 X (3/16) = 0.49 moles
Here, the molecular mass of is 256.8 g
multiplying it with the number of 0.49 moles we get, 256.8 X 0.49 = 125.7 g of .
Hence, 125.7 g of will be produced.
Alpha particle has a mass of 4 (Two protons and two neutrons)
Neutron has a mass of 1
Beta particle has a mass of about 0 (Electron)
Proton has a mass of 1
So the answer is (2) Beta particle
