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:
Some policies they might do is to put limits on water usage, like making sure that people don't use too much water in baths and when they are tending to their gardens.
<u>Question in English : </u>
<span>
<em>An atom X has 8 neutrons and its atomic number equals 8. Knowing that this atom is isotopes of Y, which has mass number 18, answer: What is the number of neutrons in atom Y?</em>
</span><span><u>Answer :</u>
</span>Isotopes are defined as the atoms which have same number of
protons but different number of neutrons of same element. Since the proton
number is same, the atomic number also same. Hence the atomic number of Y is 8.
Mass number = atomic number + neutron number
18 = 8 + neutron number
Neutron number = 10
Hence, there are 10 neutrons in Y.
Answer:
Beryllium-9 is the isotope of beryllium with relative atomic mass 9.
KOH added : 7.5 ml
<h3>Further explanation</h3>
Buffer solution of weak acid HCOOH and strong base KOH
Reaction
initial = 100 ml 0.1 M HCOOH = 10 ml mol HCOOH, and x mlmol of KOH
KOH + HCOOH ⇒ COOHK + H₂O
x 10
x x x x
- 10-x x x
[HCOO - ] = 3[HCOOH]
