Top answers

1 dm^3 of water steam at 200 degrees C, 10 bar enters a compressor. When it leaves, its temperature is 400 deg. C and volume 0.5 dm^3. Calculate the final pressure of steam. Critically discuss the assumptions you made in your calculations.

This question refers to the behavior of gases under compression. In IB we model such situations using the ideal gas equation, which states that: pV = nRT, where: p - pressure of the gas V – its volume n – nu...
MM
Answered by Marcin M. • Physics tutor
4057 Views

Sort the following substances MgO, Na, H2O, H2S, NaCl, in the order of increasing melting temperature.

This question deals with the properties of substances and how they relate to their internal structure. First, we of course need to understand what the property we are asked to evaluate means. Melting tempera...
MM
Answered by Marcin M. • Chemistry tutor
15759 Views

In a lottery, 6 numbered balls are drawn from a pool of 59. Calculate the probability of scoring a jackpot. There used to be 49 balls in the pool. Calculate by how much the addition of 10 balls has decreased the probability of scoring a jackpot

The question has to do with probability, and the branch of mathematics which models such situations is called probability theory. A jackpot is, of course, when we correctly predict all the numbers on the bal...
MM
Answered by Marcin M. • Maths tutor
13219 Views

Explain how a nerve impulse passes along a non-myelinated neuron

Nerve impulses are electrical impulses that travel along the axons of nerve cells (neurons) carrying various information. Propagation of electricity is possible due to differences in electrical potential bet...
PS
Answered by Paula S. • Biology tutor
60471 Views

What mass of carbon dioxide is produced from burning 100 grams of ethanol in oxygen according to this reaction: C2H5OH + 3 O2 --> 2 CO2 + 3 H2O

Firstly, make sure the equation is correctly balanced – which it is here; comparing right sight with left: Left=Right i.e.: 2 carbon atoms, 6 hydrogen a, 7 oxygen a Next make it clear what is your unknown, s...
PS
Answered by Paula S. • Chemistry tutor
70551 Views