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For the reaction (hydrochloric acid + magnesium -> magnesium chloride + hydrogen) what would happen to the rate of reaction if the solid magnesium was cut into smaller pieces? Explain the change (4)

By cutting the solid magnesium into smaller pieces you are increasing the surface area and also making a larger surface area to volume ration. Increasing the surface area increases the rate of reaction as...

Answered by Abigail R. • Chemistry tutor

6558 Views

Find 100 consecutive natural numbers, each of which is composite

So this is the sort of quesition where you will spend a while thinking about it, probably feel a little silly you haven't gotten it yet, then go "aha!", write down the answer and move on. It's a...

Answered by Gabriel V. • STEP tutor

952 Views

If x^2 + 2y = -14 and y = 4x + 1 , by using the quadratic formula, find the possible values for x.

First the equation for y must be substituted into the first equation to give a quadratic equation in x. Rearrange this equation so that the left-hand side equals 0. Using the quadratic formula the possibl...

Answered by Rachael W. • Maths tutor

2301 Views

Calculate the enthalpy of combustion of 1 mol of ethanol using mean bond enthalpy (kJ/mol) data: C-C (347), C-H (413), C-O (358), O-H (464), O=O (498), C=O (805)

First we need to construct the equation of the combustion: C2H5OH(l) + 3O2(g) --> 2CO2(g) + 3H2O(l)Use aid of structural formulaLeft hand side (endothermic - requires energy):5(413) + 347 + 358 + 464 +...

Answered by Lewis L. • Chemistry tutor

9368 Views

What is phototropism?

Phototropism is the directional growth of a plant in response to a light stimulus.If it grows towards the light then it is positive (the most common type of phototropism)...

Answered by Sacha J. • Biology tutor

2072 Views