When repeated measurements of the same quantity are very close to one another they are termed as precise measurements.
<u>Explanation:
</u>
An experiment is repeated two to three times and the outcomes were checked to have similar values to attain precision of the measurements. The accuracy and precision are the important in attaining correct measurements.
The accuracy is the closest true value obtained from the measuring instrument. But to get precise results, the measurements were taken repeatedly and then analyzed whether the values obtained are similar or varying significantly.
If the repeatedly measured values are very close to one another that means the measured quantities are precisely taken. All the values are precise in nature.
Answer:
Option C = object B by 1 gram per cubic cm.
Explanation:
Given data:
Mass of object A = 12 g
Volume of object A = 8 cm³
Mass of object B = 20 g
Volume of object B = 8 cm³
Densities = ?
Solution:
Density:
Density is equal to the mass of substance divided by its volume.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Density of object A:
d = m/v
d = 12 g/ 8 cm³
d = 1.5 g/cm³
Density of object B:
d = m/v
d = 20 g/ 8 cm³
d = 2.5 g/cm³
object b has high density.
Answer:
5.95g
Explanation:
1 
= 1000 mL
∴ 100 mL = 100 ÷ 1000 = 0.1
Volume = <u>0.1 </u><u />
Concentration = <u>0.5 M</u>
Concentration = 
0.5 = 
No. of moles = 0.5 x 0.1 = <u>0.05 moles</u>
No. of moles = 
Mass in 1 mole of KBr = 39 + 80 = 119g (39 is the mass of potassium and 80 is the mass of bromine)
0.05 = 
x = 119 × 0.05 = 5.95g
