Answer:
11.7 mL
Explanation:
Density of a substance is given by the mass of the substance divided by the volume of the substance .
Hence , d = m / V
V = volume
m = mass ,
d = density ,
From the question ,
The density of the metal = 10.5 g/cm³
The mass of the metal = 5.25 g
Hence , the volume can be calculated from the above formula , i.e. ,
d = m / V
V = m / d
V = 5.25 g / 10.5 g/cm³
V = 0.5 cm³
Since , The unit 1 mL = 1 cm³
V = 0.5 mL
The vessel has 11.2 mL of water ,
The new volume becomes ,
11.2 mL + 0.5 mL = 11.7 mL
Answer:
1 g
Explanation:
The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.
We can make a table of the mass left after each half-life.

The mass remaining after 48 h is 1 g.
A: adenine
C: cytosine
g: guanine
t: thymine
Anywhere between 5sogt2 and 776sogt2
First equation:
molarity=
no.of moles of solute (Na2S)/volume of solution
0.300/1.75 = 0.171
second equation:
same law
but in volume it is milliliter so you have to convert it by multiplying it with 10^-3
(10 power -3)
to understand it clearly
see this
http://imgur.com/xTS35QM