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Do particles expand when heated?

When an object is solid, the particles have little energy and are closely packed together. When you heat an object, the particles gain energy and begin to move more frequently and randomly. This means tha...

Answered by Mai T. • Maths tutor

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What is the process of protein digestion?

First of all, once proteins reaches stomach, HCL (Hydrochloric acid) due to its high acidity partially denatures proteins and activates pensinogen (secreted by the gastric glands) into an enzyme pepsin. W...

Answered by elena k. • Biology tutor

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How do you conjugate the verb "hablar" (to speak) into the preterite tense?

The rule for regular verbs in the preterite tense requires you to add the correct endings to the stem of the verb ('Hablar' - 'Habl'):habléhablastehablóhablamoshablasteishablaron

Answered by Florence J. • Spanish tutor

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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

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3A + 4B =32 6A-2B=14 work out the values of A and B

First we need to get either an equal number of As, an opposite number of As. An equal number of Bs or an opposite number of Bs. 6A-2B= 14 (Multiply by 2) 12A-4B =28 and 3A +4B =32 add together15A=60 (divi...

Answered by Oliver R. • Maths tutor

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