The number is written in scientific notation.
The significant figures are the numbers known precisely plus 1 digit that is uncertain.
When the numbers are expressed in scientific notation all the digits before 10^n are significant.
So, 7 and 8 are significant figures and the answer is that the number of significant figures is 2.
Answer: 2
The increase of the boling point of a solution is a colligative property.
The formula for the increase of the normal boiling point of water is:
ΔTb = Kb * m
Where m is the molallity of the solution and Kb is the molal boiling constant in °C/mol.
ΔTb = 0.51 °C / m * 0.100 m = 0.051 °C.
So, the new boiling temperature is Tb = 100°C + 0.051°C = 100.051 °C.
Answer: 100.051 °C
Answer:
[EtOH] = 2.2M and Wt% EtOH = 10.1% (w/w)
Explanation:
1. Molarity = moles solute / Volume solution in Liters
=> moles solute = mass solute / formula weight of solute = 9.8g/46g·mol⁻¹ = 0.213mol EtOH
=> volume of solution (assuming density of final solution is 1.0g/ml) ...
volume solution = 9.81gEtOH + 87.5gH₂O = 97.31g solution x 1g/ml = 97.31ml = 0.09731 Liter solution
Concentration (Molarity) = moles/Liters = 0.213mol/0.09731L = 2.2M in EtOH
2. Weight Percent EtOH in solution (assuming density of final solution is 1.0g/ml)
From part 1 => [EtOH] = 2.2M in EtOH = 2.2moles EtOH/1.0L soln
= {(2.2mol)(46g/mol)]/1000g soln] x 100% = 10.1% (w/w) in EtOH.
The answer is 27.92g . working is shown in the picture above.
I am pretty sure that the answer is B. extrusive rock. I hope that this helps you!! Good Luck!!
