Answer:
This process is known as doping. It can be done by adding either of two types of impurity to the crystal. (A) By adding electron rich impurities i.e., group 15 elements to the silicon and germanium of group 14 elements.
Answer:
Water's polarity and its ability to form hydrogen bonds give it special properties, including adhesion, cohesion, and the ability to moderate temperature.
Answer:
- <em>1.34 × 10²⁴ molecules</em>
Explanation:
To calculate the <em>number of molecules of sodium oxide that will be created if 275 grams of sodium reacts with excess oxygen</em>, use the chemical equation to calculate the number of moles and then multiply by Avogadro's number.
<u>1) Balanced chemical equation (given):</u>
<u>2) Mole ratio:</u>
<u>3) Calculate the number of moles in 275 g of Na:</u>
- n = mass in grams / molar mass
- mass of Na = 275 g
- molar mass of Na₂O = 61.9789 g/mol
- n = 275 g / 61.9789 g/mol = 4.437 mol of Na
<u>4) Set a proportion to find the number of moles of product (Na₂O):</u>
- 2 mol Na₂O / 4 mol Na = x / 4.437 mol Na
- x = 4.437 / 2 mol Na₂O = 2.2185 mol Na₂O
<u>5) Convert the number of moles to number of molecules:</u>
- # molecules = n × 6.022 × 10²³ molecules/mol = 2.2185 mol × 6.022 × 10²³ molecules/mol = 1.34 × 10²⁴ molecules (rounded to 3 significant figures).
Answer: (3) silicon
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Silicon (Si)
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: ethane 
, propanone 
and water 
In the bookstore Avanti gave four books so it would be 1
