Answer:
All of these three are polar molecules or ions
Explanation:
1) CO3 ^2-
It is a polar ion because it consists of one Oxygen atom and three carbon atoms so there is a substantial electroegativity difference between carbon and Oxygen due to which shared electrons are attracted more towards Oxygen creating partial negative charge on it and less towards carbon creating a partial positive charge on it, which makes the overall ion polar.
2) HCN
HCN is a polar molecule because there is substantial electronegativity difference between Carbon and Hydrogen as well as between Carbon and Nitrogen. Due to this negative charge is induced over Nitrogen because electronegativity of Nitrogen is 3.0 and positive charge on Carbon because its electronegativity is 2.5. The overall molecule is polar.
3) NO3^-1
Nitrate ion is also a polar molecule because there are three atoms of Oxygen and one atom of Nitrogen. There is substantial electronegativity difference between oxygen (3.44) and nitrogen (3.0) due to which partial positive charge is created on Nitrogen and partial negative charge created over three Oxygen atoms. The overall molecule is polar.
Hope it helps!
Below is the list of enthalpies of formation of the compounds involved in the chemical reaction.
HCl: -92.3 kJ/mol
H2: 0
Cl2: 0
Both H2 and Cl2 do not have enthaply of formation because they are pure substances.
Since, in the reaction there are 2 moles of HCl,
Enthalphy of formation = enthalpy of products - enthalphy of reactant/s
= 0 - (-92.3)(2) = +184.6 kJ
Hence, the answer is the first choice.
Answer:
185.92 L
Explanation:
Given data:
1 mole = 6.022× 10²³ molecules
1 mole = 22.4 L
Volume occupy by 5.0× 10²⁴ molecules
Solution:
1 mole = 6.022× 10²³ molecules
5.0× 10²⁴ molecules × 1 mole / 6.022× 10²³ molecules
0.83× 10¹ mol
8.3 moles
1 mole occupy 22.4 L
8.3 mol × 22.4 L / 1 mol
185.92 L
Hello!
To do this, use the molar mass. This is how much a mole of an atom weighs. A mole is 6.02214076×10²³ atoms.
Molar masses of:
Se: 78.96 g/mol
Cu: 63.546 g/mol
Ba: 137.327 g/mol
Now, the element with the highest molar mass will have the fewest atoms. This is because the element weighs more, so therefore for the same amount of mass, there will be less of the element needed to reach that mass.
Therefore, 10g of Ba would have the fewest number of atoms.
Hope this helps!
