Answer:
Because of the less reactivity of copper.
Explanation:
As well as being resistant to the elements and thereby less likely to be affected by rainfall, hail, and mildew than other types of roofing, copper is also one of the most fireproof materials available. Copper is also highly resistant to thermal changes and thereby doesn't deteriorate quickly.
Magnesium would also corrode PDQ. Magnesium sheeting would also pose an unacceptably high fire hazard.
Answer:
A single compound is simultaneously oxidized and reduced.
Explanation:
In chemistry, disproportionation is a simultaneous oxidation and reduction of a single chemical specie.
What this means is that; in a disproportionation reaction, only one compound is both oxidized and reduced. This implies that two products are formed during disproportionation. One is the oxidized product while the other is the reduced product.
Consider the disproportionation of CuCl shown below;
2CuCl -----> CuCl2 + Cu
Here, CuCl2 is the oxidized product while Cu is the reduced product.
Answer:
If anything but H2O were found, it would be evidence of a chemical change. Therefore, 4 is the only viable evidence that it was a physical change of H2O liquid to H2O gas.
A physical change is any change in a substances form that does not change its chemical makeup. Examples of physical changes are breaking a stick or melting ice. A chemical change occurs when atoms of a substance are rearranged, and the bonds between the atoms are broken or formed. HOPE THIS HELPS!!
Speed in km/hr = 15 x 18
------------
5
= 54 km/hr.
Hope this helps!
