Answer:
A system of knowledge and the methods to find that knowledge is Science.
Answer:
0.6 moles of CaO will produced.
Explanation:
Given data:
Mass of calcium = 23.9 g
Moles of CaO produced = ?
Solution:
Chemical equation:
2Ca + O₂ → 2CaO
Number of moles of calcium:
Number of moles = mass/ molar mass
Number of moles = 23.9 g / 40 g/mol
Number of moles = 0.6 mol
Now we will compare the moles of calcium and CaO.
Ca : CaO
2 : 2
0.6 : 0.6
0.6 moles of CaO will produced.
The correct is D.
Water is a polar molecule and it has polar bonds, which carry partially positive and partially negative charges. This polar bond increases the attraction between molecules of water and thus it requires a greater energy to break the bond between the molecules of water compare to carbon dioxide, which is a non polar molecule. Thus, water has a higher boiling point than carbon dioxide.
1.2*10^24# atoms of chlorine
Explanation:
Chlorine gas (#Cl_2#) has two atoms of elemental chlorine in a molecule, so:
#1# mol of #Cl_2# have #6*10^23# molecules of #Cl_2#
#1# molecule of #Cl_2# have #2# atoms per molucule
Then #2*6*10^23 = 1.2*10^24# atoms of chlorine in a mol of chlorine gas
Answer:
Fe(CN)₂, FeCO₃, Pb(CN)₄, Pb(CO₃)₂
Explanation:
Cations (positively charged ions) can only form ionic bonds with anions (negatively charged ions). However, you can't just simply put one cation and one anion together to form a compound. Each compound needs to been neutral, or have an overall charge of 0. When cations and anions do not have charges that perfectly cancel, you need to modify the amount of each ion in the compound.
1.) Fe(CN)₂
-----> Fe²⁺ and CN⁻
-----> +2 + (-1) + (-1) = 0
2.) FeCO₃
-----> Fe²⁺ and CO₃²⁻
-----> +2 + (-2) = 0
3.) Pb(CN)₄
-----> Pb⁴⁺ and CN⁻
-----> +4 + (-1) + (-1) + (-1) + (-1) = 0
4.) Pb(CO₃)₂
-----> Pb⁴⁺ and CO₃²⁻
-----> +4 +(-2) + (-2) = 0