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Calculated the Relative Molecular Mass of calcium (II) chloride using the periodic table.

Calcium (II) has a charge of 2+ and each chloride has a -1 charge giving a formula of CaCl2 when balancing the charges out. Ca (Relative Atomic Mass) = 40.08 and Cl (Relative Atomic Mass) = 35.45So Relati...

Answered by Gabriel L. • Chemistry tutor

8617 Views

Source A opposes Germany. How do you know?

We know source A opposes Germany as the nation is depicted as a criminal in the cartoon. As the victors of the First World War, the allies clearly viewed Germany as a criminal and themselves to be the bri...

Answered by Hugo N. • History tutor

3897 Views

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

2456 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

1919 Views

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

2005 Views