Answer:
Explanation:
solar cell - converts sunlight into electricity
geothermal energy - heat produced within the Earth
wave energy - turns turbines along coastlines
hydroelectricity - water falling through dams turns turbines, generates electricity
1. a) Igneous.
2. c) Metamorphic.
3. b) It broke into sediment and then compacted.
4. d) All types of rocks.
5. a) Wind and rain break down the rock into small pieces.
6. a) Yes, but it should be subtuced first.
7. c) Earth's interior.
8. c) Water.
9. b) Magma is molten rock within the Earth; lava is molten rock on the Earth's surface.
Answer:
Density, melting point. and magnetic properties
Explanation:
I can think of three ways.
1. Density
The density of Cu₂S is 5.6 g/cm³; that of CuS is 4.76 g/cm³.
It should be possible to distinguish these even with high school equipment.
2. Melting point
Cu₂S melts at 1130 °C (yellowish-red); CuS decomposes at 500 °C (faint red).
A Bunsen burner can easily reach these temperatures.
3. Magnetic properties
You can use a Gouy balance to measure the magnetic susceptibilities.
In Cu₂S the Cu⁺ ion has a d¹⁰ electron configuration, so all the electrons are paired and the solid is diamagnetic.
In CuS the Cu²⁺ ion has a d⁹ electron configuration, so all there is an unpaired electron and the solid is paramagnetic.
A sample of Cu₂S will be repelled by the magnetic field and show a decrease in weight.
A sample of CuS will be attracted by the magnetic field and show an increase in weight.
In the picture below, you can see the sample partially suspended between the poles of an electromagnet.
Answer: d :The blue and orange soccer balls; they have more mass than the black soccer ball, but changed speed by the same amount.
Answer:
0.15 l of 4.0 m stock KCl solution should betaken
Explanation:
N1V1=N2V2
6*0.1=V2*4
V2=0.15L