Answer:
New Moon, First Quarter, Full Moon, Last Quarter, Waxing Crescent, Waxing Gibbous, Waning Gibbous, and Waning Crescent.
Answer:
1.022ppm is the unknown concentration of the metal
Explanation:
Based on Lambert-Beer law, the increasing in signal of a detector is directly proportional to its concentration.
The unknown concentration (X) produces a signal of 0.255
99mL * X + 1mL * 100ppm / 100mL produces a signal of 0.502
0.99X + 1ppm produce 0.502, thus, X is:
0.255 * (0.99X + 1 / 0.502) =
X = 0.503X + 0.508
0.497X = 0.508
X =
1.022ppm is the unknown concentration of the metal
Answer:
235 g
Explanation:
From the question;
- Volume is 400.0 mL
- Molarity of a solution is 4.25 M
We need to determine the mass of the solute K₂CO₃,
we know that;
Molarity = Number of moles ÷ Volume
Therefore;
First we determine the number of moles of the solute;
Moles = Molarity × volume
Moles of K₂CO₃ = 4.25 M × 0.4 L
= 1.7 moles
Secondly, we determine the mass of K₂CO₃,
We know that;
Mass = Moles × Molar mass
Molar mass of K₂CO₃, is 138.205 g/mol
Therefore;
Mass = 1.7 moles × 138.205 g/mol
= 234.9485 g
= 235 g
Thus, the mass of K₂CO₃ needed is 235 g
Answer:
The mixture of B and C will melt as 130 - 139 ºC.
Explanation:
If the melting point (130 - 139 ºC) of a mixture of A and B is lower than the pure substances that is 149 - 150 ºC that means that one of these susbtances is an impurity because reduces the melting point.
If the melting point of the mixture of A and C is the same as the pure substances, we can deduce that they are the same substances, also because the melting point when a substance is pure is just 1 or 2 ºC like in this case.
So in a Mixture of B and C is going to be like the first case of the mixture among A and B, because the B substance is the impurity.
Answer : The distance covered by slow snail in 24 hours is 
Explanation :
As we are given that the a slow snail can travel 2.2 cm in 1 minute. Now we have to calculate the distance covered by slow snail in 24 hours.
First we have to convert 24 hours in minutes.
Conversion used : (1 hour = 60 minutes)
As, 1 hour = 60 minutes
So, 24 hour = 24 × 60 minutes
= 1440 minutes
Now we have to calculate the distance covered by slow snail in 24 hours.
In 1 minute, the distance covered by slow snail = 2.2 cm
In 1440 minute, the distance covered by slow snail = 1440 × 2.2 cm
= 3168 cm
= 
Now we have to convert 'cm' into 'pm'.
Conversion used : 
As,
So, 
Therefore, the distance covered by slow snail in 24 hours is
