Answer:
The correct option is : Their atoms have eight electrons in their valence shells, so noble gases are very unreactive.
Explanation:
The octet rule state that atoms tend to complete their last energy levels with eight electrons, and that this configuration make them very stable and unreactive.
Noble gases are characterized as unreactive atoms, and this is associated with the fact that they have a complete valence shell, it means that they have eight electrons on it (they follow the octet rule).
Atoms with less electrons on their valence shells tend to react with another atom, forming bonds, to complete their valence shells (with eight electrons).
Answer:
Explanation: The equation that relates resistance of tungsten at different temperatures is as follows
R = R₀ [1 + α ∆T] , R₀ is resistance at lower temperature , R is resistance at higher temperature . α is temperature coefficient of resistivity and ∆T is rise in temperature .
Putting the values
170 = 26 [1 + .0045 ∆T]
∆T = 1230.75
lower temperature = 40◦C
higher temperature = 1230 + 40
= 1270◦C
The term metabolic syndrome defines a group of risk factors which determine your risk for health issues such as heart disease, a stroke and diabetes. Abdominal weight gain (a), elevated blood fat (c) and insulin resistance (d) are all characteristics which will increase your risk of the above health issues. The only characteristic that will decrease your risk of heart disease, diabetes and a stroke is reduced blood pressure (b). If you have any of these negative characteristics, it is important to work at reducing them; thereby, improving your health.
It has to lose electrons to become positively charged, so it can attract a negatively charged oxygen ion.
