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How do you make a buffer?

A buffer is a mix of an excess of weak acid and its salt. Buffers can be made in two ways- by mixing the weak acid with its salt or by partially neutralising the weak acid with base. 1- Making buffers by ...

Answered by Abigail J. • Chemistry tutor

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why does silicon dioxide have such a high melting/boiling point?

It has a giant lattice structure, strong covalent bonds are difficult to break etc.

Answered by Kian D. • Chemistry tutor

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1. X with 2,4-DNPH forms a red precipitate. 2. X reduces blue Copper ions into red precipitate. What kind of compound is X?

X with 2,4 DNPH (Brady's reagent) is used to show the presence of an aldehyde or ketone. X also reduces Copper ions (Fehling's) meaning it has to be an aldehyde and not a ketone as ketones are not readily...

Answered by Tom A. • Chemistry tutor

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Elemental analysis of a carbohydrate X showed the sample contained 48.7 % carbon and 8.1 % hydrogen by mass. Find the empirical formula of X.

These sorts of questions can look difficult, but if you learn the steps needed to solve them then they are all very similar.Step 1: Since we are told that X is a carbohydrate, we know tha...

Answered by Jack B. • Chemistry tutor

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2NaNO3 --> 2NaNO2 + O2. When a sample of solid sodium nitrate was heated 96cm3 of gas was collected, calculate the mass of NaNO3 Decomposed

We know that the reaction is a 2:1 ratio as 2 moles of NaNO3 is used to form 1 mole of O2 so first we need to find the moles of the product produced
SoVolume of gas (dm3)= number of moles x 24dm3The...

Answered by Sara Z. • Chemistry tutor

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