Liquid + Solid = 8.89 mL
V ( Solid ) = 8.89 mL - 6.26 mL = 2.63 mL
The density of the solid = m / V = 10.283 g / 2.63 mL =
= 3.9 g/mL = 3.9 g / cm³
Answer:
-10778.95 J heat must be removed in order to form the ice at 15 °C.
Explanation:
Given data:
mass of steam = 25 g
Initial temperature = 118 °C
Final temperature = 15 °C
Heat released = ?
Solution:
Formula:
q = m . c . ΔT
we know that specific heat of water is 4.186 J/g.°C
ΔT = final temperature - initial temperature
ΔT = 15 °C - 118 °C
ΔT = -103 °C
now we will put the values in formula
q = m . c . ΔT
q = 25 g × 4.186 J/g.°C × -103 °C
q = -10778.95 J
so, -10778.95 J heat must be removed in order to form the ice at 15 °C.
First, we are using the ideal gas law to get n the number of moles:
PV = nRT
when P is the pressure = 748 mmHg/760 = 0.984 atm
V is the volume = 4 L
R is ideal gas constant = 0.0821
T is the temperature in Kelvin = 300 K
∴ n = 0.984atm*4L/0.0821*300
= 0.1598 moles
when the concentration = moles * (1000g / mass)
= 0.1598 * (1000g / 58 g )
= 2.755 M
when the freezing point = 5.5 °C
and Kf = - 5.12 °C/m
∴ the freezing point for the solution = 5.5 °C + (Kf*m)
= 5.5 °C - (5.12°C/m * 2.755m)
= -8.6 °C
Answer:
<em>6960000 Nickel atoms</em>
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Explanation:
radius = 125 pm = 125 x 10^-12 m
diameter of each atom = 125 pm x 2 = 250 pm = 250 x 10^-12 m
span of distance to be achieved = 1.74 mm = 1.74 x 10^-3 m
number of nickel atoms = (1.74 x 10^-3 m)/(250 x 10^-12 m) = <em>6960000 Nickel atoms</em>
Answer:
Independent Variable: Grade Level
Dependent Variable: Growth in height
Hypothesis: Students in [Insert the grade level you believe will grow the quickest here] will experience the quickest growth in height.
Explanation:
Independent variables are the factors in which you manipulate to gain your results, in this case you would be changing the grade level you would observe to see the height.
Dependent variables are the factors that respond to changes in the independent variables. You don't control these events, you simply observe them. In this case, you merely observe the growth in height in accordance to the different grade levels you observe.
For the hypothesis, you would create your own hypothesis based on a guess you have. You create a hypothesis not based on the data, but on what you believe will be correct before doing the experiment. It doesn't have to be the correct answer, but just your thoughts.