It is a physical change when cream mixes with
coffee, it changes the color of the coffee. When you add more or less cream there
is a color change depending on the consistency of cream. The
properties are not changes and a no new compound is formed as in chemical
change with a reaction of two compounds, a new compound is formed with
different properties. So it is a physical change.
The solid compound, K2SO4 contains a cation called K+ and an anion called SO42-. In this case, there are 2 atoms of potassium, 1 atom of sulfur and 4 moles of oxygen. The compound also contains ionic bonds because of the composing non-metals and metal.
Answer:
Explanation:
Kory goes outside to grill some hamburgers. He tells Ethan that when you cook meat, a chemical reation is taking place. Ethan says "That's perpostrous!" Is Kory Correct??
absolutely Kory is correct
evidence of a chemical reaction are
new odor and or taste
change in color
signs of bubbling
direct effect of temperature on rate of change
evidence of a new substance being formed
we observe all these when we grill meat.
Explanation:
Agricultural productivity is dependent on Co2, Temperature, Solar Radiation, Precipitation, Soil Moisture and Wind Direction. Changes in any or all of these elements has a direct impact on the crop production.
The copper wire was sanded before burning in order to make sure that copper metal was exposed on the surface of the wire.
Answer: B
Explanation
The copper wire when placed in atmosphere without coating leads to oxidation of copper metal with respect to the impurities present in the atmosphere.
As copper is electropositive in nature, so electronegative ions present in the universe will try to react with copper and the copper will react easily with other elements.
So generally copper wire is coated with color or polymer coating.
In this case, the copper wire without any coating is sanded, so that the eddy sheets or polishing materials on friction with copper wire will remove the impurities by the electrostatic law of conservation of charges and charge transfer.
As the impurities are removed when copper wire is sanded, the copper atoms will be exposed on the surface of the wire leading to burning of copper in the copper wire.
