Answer:
70.77 g/mol is the molar mass of the unknown gas.
Explanation:
Effusion is defined as rate of change of volume with respect to time.
Rate of Effusion=
Effusion rate of oxygen gas after time t = 
Molar mass of oxygen gas = M = 32 g/mol
Effusion rate of unknown gas after time t = 
Molar mass of unknown gas = M'
The rate of diffusion of gas, we use Graham's Law.
This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:
M' = 70.77 g/mol
70.77 g/mol is the molar mass of the unknown gas.
Compound 1: Sodium borohydride
In sodium borohydride (NaBH4), B is a central metal.
Electronic configuration of B is 1s2 2s2 2p1.
B undergoes sp3 hybridization in NaBH4, to generate 4 hybrid orbitals. These hybrid orbitals, forms sigma bond with 4 'H' atoms. Due to this, the structure of sodium borohydride in tetrahedral.
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Compound 2: B<span>oron trifluoride
</span>In boron trifluoride (BF3), B is a central metal.
Electronic configuration of B is 1s2 2s2 2p1.
B undergoes sp2 hybridization in NaBH4, to generate 3 hybrid orbitals. These hybrid orbitals, forms sigma bond with 3 'H' atoms. Due to this, the structure of <span>boron trifluoride</span> is <span>triangular planner</span>.
Answer:
chemical
Explanation:
Some bronze objects tarnish to a dark brown color. Chemical properties can be identified by the changes they produce. The change of one substance into another substance is called a A piece of wood burning, an iron fence rusting, and a silver spoon tarnishing are all examples of chemical changes.
Answer:
ΔHrxn = [(1) -1675.5 ( kJ/mole) + (2) 0 ( kJ/mole)] - [(1) -824.3 ( kJ/mole) + (2) 0 ( kJ/mole)]
Explanation:
ΔHrxn = 2ΔHf (Al₂O₃) - ΔHf (Fe₂O₃)
Remember that for pure elements in their standard state of temperature and pressure by definition their standard heats of formation are zero.
ΔHrxn = 2(-1675.7) - (-824.3) kJ/mol
ΔHrxn = 2527 kJ/mol
