Given :
A student has a 1 g sample of each of the following compounds: NaCl, KBr, and KCl.
To Find :
The samples in order of increasing number of moles in the sample.
Solution :
Molecular mass of NaCl, KBr, and KCl is 58.5 g/mol , 119 g/mol and
74.5 g/mol respectively .
Moles of NaCl , 
.
Moles of KBr , 
.
Moles of KCl , 
.
The order of moles in increasing order is :
KBr , KCl and NaCl .
Hence , this is the required solution .
Saturated fats have single bond between the carbon atoms, this makes them a solid at room temperature. Unsaturated fats have at least one double bond between the carbon atoms, which makes them liquid in room temperature.
Answer:
Is not possible to make a buffer near of 7.
Optimal pH for sulfate‑based buffers is 2.
Explanation:
The dissociations of H₂SO₄ are:
H₂SO₄ ⇄ H⁺ + HSO₄⁻ pka₁ = -10
HSO₄⁻ ⇄ H⁺ + SO₄²⁻ pka₂ = 2.
The buffering capacity is pka±1. That means that for H₂SO₄ the buffering capacity is in pH's between <em>-11 and -9 and between 1 and 3</em>, having in mind that pH's<0 are not useful. For that reason, <em>is not possible to make a buffer near of 7.</em>
The optimal pH for sulfate‑based buffers is when pka=pH, that means that optimal pH is <em>2.</em>
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I hope it helps!
PbO2
You have to take the mass of lead in the problem, and divide by the molar mass.
When you do the same with oxygen, you get a number about twice as large as when you divide the mass of lead by the molar mass of lead. This means that the simplest formula would be PbO2
Answer:
This would support Dalton's postulates that proposed the atoms are indivisible because no small particles are involved.
Explanation:
Experiment using the gas discharge tube by J.J Thomson led to the discovery of cathode rays which are now known as electrons.
Primarily, Thomson's experiment led to the discovery of cathode rays, electrons, as subatomic particles.
If the size of the atoms observed at the cathode is the same as that of the rays,we can conclude that the particles of the rays are the simplest form of matter we can have. This would suggest that the atom is indeed the smallest indivisible particle of a matter according to Dalton.
