A calibration error could lead to this result, if the pH probe was not properly calibrated before being used, the measured value of pH would be different from the actual pH value. Meaning in this case the student correctly prepared the buffer.
While measuring the mass of the buffer's acid component (for example NaH₂PO₄), the student did not properly set the balance to zero before proceding to weigh the compound, causing the mass readings to be underestimated. As a result, the student weighed more acid than required, eventually leading to a decreased pH value.

6 0

4 years ago

Describe how sodium conducts thermal energy. [3 Marks]

Vera_Pavlovna [14]

In metals, some of the electrons (often one per atom) are not stuck to individual atoms but flow freely among the atoms. Of course, that's why metals are such good conductors of electricity. Now if one end of a bar is hot, and the other is cold, the electrons on the hot end have a little more thermal energy- random jiggling- than the ones on the cold end. So as the electrons wander around, they carry energy from the hot end to the cold end, which is another way of saying they conduct heat.

Here, sodium is a metal which possesses an extra (valence) electron carries the heat around its body as it is a free electron, which enables sodium to conduct thermal energy.

Hope this help :)

3 0

3 years ago

Please help with this

Alex787 [66]

C metamorphic rock
Why: because o know

7 0

3 years ago