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An excess of Lead (II) oxide reacts with 175cm3 of 1.5 mol dm3 nitric acid. Calculate the maximum quantity of lead that can be obtained from this reaction.

Write the equation: PbO + HNO₃ --> PbNO₃ + H₂O. Balance the equation: there are two moles of hydrogen (in water) on the right. To bala...

Answered by Hibba S. • Chemistry tutor

9326 Views

What are the advantages of making voting compulsory in the UK? (10 Marks)

As evidenced in liberal democracies where compulsory voting is a federal law, this has had a positive impact on political participation and has been proposed by campaigners such as Graham...

Answered by Hugh D. • Government and Politics tutor

4891 Views

Using Newton's law of universal gravitation, show that T^2 is proportional to r^3 (where T is the orbital period of a planet around a star, and r is the distance between them).

Newton's law of gravitation is: F_G=(GMm)/(r²).First of all, it's a good idea to draw a diagram of the planet and star, labelling the directions of the centripetal force and and the p...

Answered by Jake B. • Physics tutor

4463 Views

What causes the aggregate demand curve to shift?

Aggregate demand is the total demand for all goods and services in an economy; it is essentially gross domestic product. Its components are consumption, investment, government spending and net exports (ex...

Answered by James W. • Economics tutor

4202 Views

Explain, with reference to the electronic transitions involved, how characteristic flame colours of metal ions are formed and why the flame colours are different.

To answer this we need to talk about how electrons move in an atom. Electrons are in energy levels (orbitals) and an electron in the highest unoccupied orbital can be excited to a higher shell when ...

Answered by Isabel K. • Chemistry tutor

5069 Views