Answer:
An element is a substance that is made up of the same kind of atoms and
cannot be broken down into simpler substances by any known chemical means
examples of element are iron boron carbon helium calcium hydrogen etc
Answer:
Explanation:
Calcium is the element of the group 2 and period 4 which means that the valence electronic configuration is ![[Ar]4s^2](https://tex.z-dn.net/?f=%5BAr%5D4s%5E2)
.
Chlorine is the element of the group 17 and period 3 which means that the valence electronic configuration is ![[Ne]3s^23p^5](https://tex.z-dn.net/?f=%5BNe%5D3s%5E23p%5E5)
.
Thus, calcium losses 2 electrons to 2 atoms of chlorine and these 2 atoms of chlorine accepts each electron to form ionic bond. This is done in order that the octet of the atoms are complete and they become stable.
Ca Cl
2 1
Cross multiplying the valency, We get,
Thus, the formula of calcium chloride is .
Answer
Manual samplers are prone to effects of temperature, speed of wind and air concentrations.
Explanation
Manual samplers face several challenges that can act as drawbacks to obtaining accurate results. They are subjected to effects of sampling duration where long sampling times are needed to obtain adequate mass for detection. Manual samplers face challenges when measuring non-volatile species because particles are observed into the adsorption medium at a slower rate of diffusion.
The first question would be B) they are examples of cell organelles. The second question would be A) mitochondria. Hope this helps!
Dimitri Mendeleev was inspired primarily by the work of Antoine Lavoisier and his work on writing the first extensive list of known elements. Lavoisier also collaborated in the construction of the metric system and worked to develop a better nomenclature for chemical compounds which parts are still used today.
