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When do you use the prepositions 'por' and 'para'?

Prepositions are used to relate a word or element in a sentence. 'para' and 'por' are the translation of 'for'. 'Para' is used when there is a destination eg. 'para ti', 'para mi', 'para nosotros'. (for y...

Answered by Patricia G. • Spanish tutor

2304 Views

What is the difference between the verbs 'ser' and 'estar'

'Ser' and 'estar' refer to the verb 'to be'. However, in Spanish the verb 'to be' can be used in different ways depending on the context. For example 'estar' refers to a an emotional state that can vary w...

Answered by Patricia G. • Spanish tutor

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Periodicity shows a fairly smooth increasing trend across a period for ionisation energy. However, between groups 2 & 3 and groups 5 & 6, the trend doesn't appear to be followed. Using your knowledge of chemistry, explain why the trend isn't followed here

For elements in group 2, their valence electrons consist of "ns²" where n is the principle quantum number/shell number. However, for elements in group 3, their valence electrons consi...

Answered by George W. • Chemistry tutor

1911 Views

Solve the equations x-y=1 and 5x-3y=13

These equations are what we call 'simultaneous' which means they are solved together. To do this, we need to make one of the variables (x or y) the subject of either of the equations.Rearranging the first...

Answered by Christopher K. • Maths tutor

4498 Views

Draw the full structual diagram of ethyl-ethanoate, labeling relevent bond angles and explain why the molecule has this structure.

(unable to draw diagram and upload in this format) ethyl ethanoate has the semi structural formula of CH3COOCH2CH3. According to electron repulsion theory the bond angle around the second carbon atom woul...

Answered by • Chemistry tutor

6726 Views