A compound is a substance made up of atoms of two or more different elements joined by chemical bonds. A mixture is a combination of two or more substances that are not chemically combined.
The blue color of copper (ii) sulfate will change to green, yellow, orange ,red and then a dark red or brown.
Glucose is a reducing sugar; reducing sugars are sugar that forms an aldehyde or ketone in the presence of an alkaline solution. Reducing sugars reduce the blue copper sulfate from the Benedict's solution to a red brown copper sulfide; which is seen as the precipitate and is responsible for the color change.
The answer will be (4) HI because the greater the difference of the bonds in electronegativity, the more polar a bond is.
<span>In the 19th century, scientists realized that gases in the atmosphere cause a "greenhouse effect" which affects the planet's temperature. These scientists were interested chiefly in the possibility that a lower level of carbon dioxide gas might explain the ice ages of the distant past. At the turn of the century, Svante Arrhenius calculated that emissions from human industry might someday bring a global warming. Other scientists dismissed his idea as faulty. In 1938, G.S. Callendar argued that the level of carbon dioxide was climbing and raising global temperature, but most scientists found his arguments implausible. It was almost by chance that a few researchers in the 1950s discovered that global warming truly was possible. In the early 1960s, C.D. Keeling measured the level of carbon dioxide in the atmosphere: it was rising fast. Researchers began to take an interest, struggling to understand how the level of carbon dioxide had changed in the past, and how the level was influenced by chemical and biological forces. They found that the gas plays a crucial role in climate change, so that the rising level could gravely affect our future. (This essay covers only developments relating directly to carbon dioxide, with a separate essay for Other Greenhouse Gases. Theories are discussed in the essay on Simple Models of Climate.)</span>
A measure of thermal energy transferred between two different bodies at different temperatures would be the correct answer. So, the third option.
