Answer:
Possible lowest volume = 0.19 cm
Possible highest volume = 0.21 cm
Explanation:
given data
volumetric pipette uncertainty = 0.01 cm³
total volume = 0.20 cm³
solution
we will get here Possible lowest and highest volume that is express as
Possible lowest volume = total volume - uncertainty .....................1
Possible highest volume = total volume + uncertainty ....................2
put here value in both equation and we get
Possible lowest volume = 0.20 cm - 0.01 cm
Possible lowest volume = 0.19 cm
and
Possible highest volume = 0.20 cm + 0.01 cm
Possible highest volume = 0.21 cm
Answer:
Promethium
Pm 61
Discovered by Jacob .A. Marinsky
Answer:
6. 7870 kg/m³ (3 s.f.)
7. 33.4 g (3 s.f.)
8. 12600 kg/m³ (3 s.f.)
Explanation:
6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.
1 kg= 1000g
1m³= 1 ×10⁶ cm³
Mass of iron bar
= 64.2g
= 64.2 ÷1000 kg
= 0.0642 kg
Volume of iron bar
= 8.16 cm³
= 8.16 ÷ 10⁶
Density of iron bar
= 7870 kg/m³ (3 s.f.)
7.
Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³
Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume
(3 s.f.)
Answer:
Molarity = 0.72M
Molality = 0.85M
Explanation:
Molarity and molality are two measures of molar concentration, and they can be calculated as follows:
Molarity = number of moles/volume of solvent
Molality = number of moles/mass (kg) of solvent
Mole = mass/molar mass
Molar mass of stilbene (C14H12) = 12(14) + 1(12)
= 168 + 12
= 180g/mol
mole of stilbene = 13/180
mole = 0.072mol
Volume = 100mL = 0.1L
molarity = 0.072/0.1
Molarity = 0.72M
Molality = number of moles ÷ mass (kg) of solvent
To get mass of solvent, we use;
Density = mass/volume
Mass = density × volume
Mass = 0.85g/mL × 100mL
Mass = 85g
Mass in kg = 85/1000 = 0.085kg
Molality = 0.072/0.085
Molality = 0.847M
Molality = 0.85M