An echocardiogram uses sound waves to produce images of your heart. This commonly used test allows your doctor to see your heart beating and pumping blood. Your doctor can use the images from an echocardiogram to identify heart disease.Depending on what information your doctor needs, you may have one of several types of echocardiograms.his commonly used test allows your doctor to see your heart beating and pumping blood. Your doctor can use the images from an echocardiogram to identify heart disease. Depending on what information your doctor needs, you may have one of several types of echocardiograms.
Explain the octet rule and give an example of how it is used. The electron configurations of the noble gases are extremely stable. The octet rule states that, in chemical reactions, elements gain or lose electrons to achieve a noble gas configuration.hen oxygen reacts to form ionic compounds, it completes its octet by gaining two electrons from the element it reacts with. These two electrons add to the p orbital of oxygen, giving it the electron configuration (1s 2s 2p) of neon.
Atoms in these periods may follow the octet rule, but there are conditions where they can expand their valence shells to accommodate more than eight electrons. Sulfur and phosphorus are common examples of this behavior. Sulfur can follow the octet rule as in the molecule SF2. Each atom is surrounded by eight electrons. It is possible to excite the sulfur atom sufficiently to push valence atoms into the d orbital to allow molecules such as SF4 and SF6. The sulfur atom in SF4 has 10 valence electrons and 12 valence electrons in SF6.