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How does sodium chloride (salt/grit) lower the freezing point of water?

Water is a highly ordered material. When something dissolves in water, some of these O-H bonds are broken. This requires heat energy. The water molecules can then form attractive interactions to solute ions ...
OO
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Work out the value of 2a^2 + b^3 when a = 5 and b = –3

It is best to approach this question in parts, then combine the parts to find your solution. This question may be split into parts, as follows: Firstly, if a = 5, then a 2 = 5 2 = 5 x 5 = 25. So a 2 = 25 Sec...
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Answered by Tutor51449 D. • Maths tutor
15062 Views

The potential difference in a circuit is 5V. There are two resistors connected in series of resistance 10 Ohms. Calculate the current I in the circuit.

Ohm's law states that V=IR ; where V is p.d., I is current and R is resistance. Firstly the two resistors are in series so the total resistance is just the sum of the two resistances. Therefore R = 10+10 = 2...
RS
Answered by Ryan S. • Physics tutor
5578 Views

5 students are in a maths class and 10 students are in a physics class. The mean mark of the maths class is 90 and the mean mark of the physics class is 85. Work out the mean mark of both classes.

To find the mean mark the formula is mean = ∑marks /number of students Therefore the mean for maths is 90 and so ∑marks = mean number of students = 90 5 = 450 and the ∑marks for the physics class is 85*10= 8...
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Answered by Ryan S. • Maths tutor
3976 Views

What type of context is relevant and how can I put this in my answer?

Generally, context can be split up into different types such as biographical (anything about the author or poet's life which links to the text), historical (events at the time of the author's writing which m...
TD
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