Answer:
1.Very good electrical conductivity :<u> Metals</u> (Decreacing order of conductivity)
- <em>Silver > Copper > Gold > aluminium</em>
2. Amphoteric <u>: Metal elements</u>
- <em>Beryllium , Aluminium , Zinc </em>,
3.Gaseous at room temperature: mostly <u>Nobel gases elements</u> and some non - metal elements.
- <em>Helium ,neon , argon , krypton , fluorine , Oxygen , nitrogen</em>
4.Solid at room temperature:<u> Mostly Metals</u> (few non-metals, metalloid elements)
- <em>Metals (Sodium , potassium , calcium , gold are solid)</em>
<em>Non- metals(Carbon ,Boron )</em>
<em>Metalloids(antimony)</em>
<em>5.</em> Brittle <em>: </em><u>non - metals </u>(can't be rolled into wires)
<em>Hydrogen , carbon , sulfur , phosphorus</em><u> </u>
Explanation:
Answer:
= 72.73%
Explanation:
The percentage by mass of an element is given by;
% element = total mass of element in compounds/molar mass of compound × 100
The mass of oxygen in carbon dioxide = 32 g
Molar mass of CO2 = 44 g
Therefore;
% of O2 = 32/44 × 100%
<u>= 72.73%</u>
Answer:
Over the past few decades, humans have released so many different chemicals into the air that they have changed the mix of gases in the atmosphere. ... In addition, the exhaust from cars, trucks, and buses releases nitrogen oxides and sulfur dioxide into the air.
Answer:
beryllium chloride
Explanation:
Therefore a compound made from beryllium and chlorine will be named beryllium chloride.
Testable, that is always required for a hypothesis. Otherwise, how can you prove it?
