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What is the mass (in grams) of 0.1 moles of CaCO3?

Use the equation mass(g) = moles x MrThe moles are given in the question, moles= 0.1 molLook at a periodic table to work out the Mr of CaCO3: Ca= 40 C= 12 O= 16 Therefore Mr= 40+12+(16x3) = 100S...

Answered by Sophie S. • Chemistry tutor

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Why can graphite conduct electricity but diamond can not?

In diamond the carbon atoms are bonded to four other atoms. Whereas, in graphite each carbon atom is only bonded to three other atoms. Therefore, there are delocalised (free) electrons in graphite, which ...

Answered by Sophie S. • Chemistry tutor

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2.4 g of magnesium reacts with 1.6 g of oxygen. What is the empirical formula of the oxide formed?

Ar of Magnesium = 24; Ar of Oxygen = 16

number of moles = mass divided by Ar

number of moles of Mg = 2.4/24 = 0.1

number of moles of Oxgen = 1.6/16 = 0.1

Answered by Katrina T. • Chemistry tutor

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Can you explain what stoichometry actually is and why the ratio is not the same as the number of moles?

Stoichiometry is just a way of relating two species that react, in a ratio. EXAMPLE: 1A + 2B -> 3C Now usually this would be written as A + 2B -> 3C but I've written the 1 to exaggerate the point. N...

Answered by Michael R. • Chemistry tutor

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