Search results

Whoever wrote that question about properties of water waves, they should be banned. "Dispersion" is not caused by "waves bending around the edges of an object". That is a description of diffraction. "Superposition" is not caused by "waves bending near an object". Dispersion is a change in the...

The answer is (C). This question has been answered before. See here: https://www.boredofstudies.org/threads/physics-revision-for-prelims-stuck-on-a-mod-1-q-%F0%9F%92%80.409710/#post-7578030

You are correct, the answer is (C). In all questions regarding relative velocities, if you are asked to find the velocity of A relative to a moving frame of reference B, rather that a stationary frame of reference, you must subtract the motion of the moving frame of reference.

The correct answer is (C). Galvanometer 'X' is normally stationary. In normal operation if a positive potential is applied to the + terminal of a galvanometer the armature/needle deflects clockwise to the right (an application of the motor effect). Now if instead the body of galvanometer 'X' is...

Evaporite minerals are sedimentary deposits that have precipitated from hot aqueous solutions. Therefore they almost invariably contain some water of crystallisation. For example, a very common evaporite mineral is hydrated gypsum, whose chemical formula is CaSO4. 2H2O. Therefore I would include...

Definitions: PARTICIPANTS: the personnel who actually have responsibility for inputting, retrieving, transmitting, processing, transforming and reporting the data in the system. Participants are people who have a stake in the efficient operation of the information system. INDIRECT USERS: the...

To understand why the position of equilibrium does not correspond to equal molar concentrations of products and reactants, this could only occur if the rates of the forward and reverse reactions are exactly matched at the equimolar concentrations. This almost never occurs. One reaction is...

For a solution to be saturated, and at equilibrium, by definition there must be some excess solid solute. It is not the amounts or the concentrations of solid and dissolved solute that are the same. In fact, we can't really talk about a concentration value for a crystalline solid. All you need...

"In the beginning God created the heaven and the Earth. And the Earth was without form, and void. and darkness was upon the face of the deep. "And God said Let the waters under the heaven be gathered together unto one place; and let the dry land appear, and it was so. "And God called the dry...

There is no single explanation for how a heterogeneous catalyst works. A heterogeneous catalyst is usually a solid (or it could sometimes be an immiscible liquid) but it presents a surface to the reactants that accelerates the rate of reaction. A good example would be a Ziegler-Natta catalyst...

The net reaction is like a hypothesis- I'm asking this question at the beginning with a chemical equation, "Can mercury be oxidised to mercury 2+ ions and copper 2+ ions be reduced to copper in a spontaneous reaction?" The answer is, "No."

All electrode potentials are defined as reduction potentials. The reduction potential of Cu2+ to Cu(s) Eo is 0.34 V and the reduction potential of Hg2+ to Hg(l) Eo is 0.85V. The reaction is non-spontaneous, mercury metal will not displace copper ions from a solution of copper sulfate. Here is...

You should recall from valence shell electron-pair repulsion theory that the bonding and the non-bonding electron pairs occupy positions as far away from each other as possible. Yes, that means the electron pairs are in a tetrahedral arrangement, but it also means the two hydrogens are in a bent...

Yes, the coefficient of friction is always a positive number. The friction force always opposes the direction of incipient motion. If you are pushing the block up the ramp, the friction force acts down the ramp, and vice versa. That's a strange way to describe the coefficient of friction, to say...

Yes, it was 2011. According to NESA, new syllabus consultation with teachers and school systems will start in 2025, syllabus written by 2027, start teaching in 2028 and first examination in 2029. It's a long slow process, so five more years of examining the current syllabus.

No, Michelson-Morley is not explicitly in the syllabus. You can't be asked questions about this experiment. The whole "luminiferous ether" model has been removed. I can only guess that their reasoning was because this experiment produced a null result, and it was not referred to by Einstein in...

The integrated peak heights are used to determine the number of protons in closely similar chemical environments. Look at those stair-step graphs. The height of the step is the integrated value. The peaks at -1.3 and -2.0 have the same step height so they represent the same number of protons...

Go to the NESA website. There is an exam archive with the examination packs for all the past papers. Here is the link for Chemistry: https://educationstandards.nsw.edu.au/wps/portal/nesa/resources-archive/hsc-exam-papers-archive/chemistry/

Well, I disagree. However, you must follow what your teacher wants because he/she is going to mark the work.

Don't be too discouraged by the inaccurate results. This is quite normal for student first-hand investigations of enthalpy of combustion. The errors are huge. You are right about the incomplete combustion causing an error; it is much more difficult to achieve complete combustion for pentan-1-ol...