Answer:
Only to elements are gases at room temperature and standard pressure.
Fluorine and chlorine.
Explanation:
The group 17 is called halogen.
There are five elements in halogen group.
All halogens required one electrons to complete the octet and to get the noble gas electronic configuration.
All halogen elements have seven valance electrons.
Halogen elements:
Fluorine, chlorine, Bromine, iodine and astatine
Fluorine is gas at room temperature which s 25°C and standard pressure which is 1 atm.
It is present in the from of F₂.
Chlorine is also gas at room temperature and standard pressure.
It is present in the from of Cl₂.
The bromine is liquid under these condition.
Iodine and astatine are solids.
As we move down the group their melting and boiling points increases.
Aluminum sulfide : Al₂S₃
ratio cation : anion = 2 : 3
<h3>Further explanation</h3>
Given
Compound of Aluminium
Required
cations anions ratio
Solution
Salt can be formed from cations and anions which have their respective charges.
In the chemical compound formula these charges are crossed with each other
For aluminum it has a +3 charge
1. Aluminum carbide : Al₄C₃
ratio cation : anion = 4 : 3
2. Aluminum chloride : AlCl₃
ratio cation : anion = 1 : 3
3. Aluminum sulfide : Al₂S₃
ratio cation : anion = 2 : 3
4. Aluminum nitride : AlN
ratio cation : anion = 1 : 1
Answer:ThE aNsWeR iS B
Explanation: The earth was one a big ocean but than volcanoes explode and that created land :)
Engine is it ok ksndjsjja
Answer:
21.3 g. Option B
Explanation:
The reaction is:
4HF(g) + SiO₂(s) → SiF₄(g) + 2H₂O(g)
We analysed it and it is correctly balanced.
4 moles of hydrogen fluoride react to 1 mol of silicon dioxide in order to produce 1 mol of silicon fluoride and 2 moles of water vapor.
We determine molar mass of each reactant:
HF → 1.01 g/mol + 19 g/mol = 20.01 g/mol
SiO₂ → 16 g/mol . 2 + 28.09 g/mol = 60.09 g/mol
We convert mass to moles: 16 g . 1 mol /60.09g = 0.266 moles of glass
Ratio is 1:4. 1 mol of glass react to 4 moles of HF
Our 0.266 moles may react to (0.266 . 4) / 1 = 1.07 moles of gas
We convert moles to mass: 1.07 mol . 20.01 g/mol = 21.3 g
