Answer: The best reason the scientific community will accept a theory is if it is proven.
Answer is: 13181,7 kJ of energy <span>is released when 10.5 moles of acetylene is burned.
</span>Balanced chemical reaction: C₂H₂ + 5/2O₂ → 2CO₂ + H₂O.
<span>ΔHrxn = sum of
ΔHf (products of reaction) - sum of ΔHf (reactants).</span><span>
Or ΔHrxn = ∑ΔHf (products of reaction)
- ∑ΔHf (reactants).
ΔHrxn - enthalpy change of chemical reaction.
<span>ΔHf - enthalpy of formation of reactants or
products.
</span></span>ΔHrxn = (2·(-393,5) + (-241,8)) - 226,6 · kJ/mol.
ΔHrxn = -1255,4 kJ/mol.
Make proportion: 1 mol (C₂H₂) : -1255,4 kJ = 10,5 mol(C₂H₂) : Q.
Q = 13181,7 kJ.
Answer
pOH = 4.1
Explanation
<em>Given:</em>
pH = 9.9
<em>Required</em>: The concentration of OH-
Solution
pH + pOH = 14
9.9 + pOH = 14
pOH = 14-9.9
pOH = 4.1
Answer:
Phosphorous has the smallest atomic size.
Explanation:
As we know these elements belong to same period means there valence shell is the same. So moving from left to right along the period the shell number remains constant but the number of protons and electrons increases. So, due to increase in number of protons the nuclear charge increases hence attracts the valence electrons more effectively resulting in the decrease of atomic size.
Elements and their atomic radius are as follow,
<span><span>Magnesium 0.160 nm
</span><span>
Aluminium 0.130 nm
</span><span>
Silicon 0.118 nm
</span><span>
Phosphorus <span>0.110 nm</span></span></span>
