Answer:
A) positive; added
Explanation:
Based on the reaction:
2NaHCO3(s) + 129kJ → Na2CO3(s) + H2(g) + CO2(g)
<em>2 moles of NaHCO3 requires 129kJ to produce 1 mole of Na2CO3, 1 mole of H2 and 1 mole of CO2.</em>
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That means, the energy must be added being, thus, an exothermic reaction. The exothermic reactions have ΔH >0.
Thus, right answer is:
A) positive; added
Hydrochloric acid + Sodium hydroxide =Sodium chloride +water
<span>N-methyl 2 pyrrolidone is a cyclic amide and it when heated with aqueous acid gives the product as a cyclic amino acid. The product name is </span><span>N-Methyl-4-aminobutyric acid</span><span>
The reaction is given as follows in the attached picture.
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Answer:
20.3 % NaCl
Explanation:
Given data:
Mass of solute = 45.09 g
Mass of solvent = 174.9 g
Mass percent of solution = ?
Solution:
Mass of solution = 45.09 g + 174.9 g
Mass of solution = 220 g
The solute in 220 g is 45.09 g
220 g = 2.22 × 45.09
In 100 g solution amount of solute:
45.09 g/2.22 = 20.3 g
Thus m/m% = 20.3 % NaCl
Answer : False, there will be two lithium and one oxygen atoms in a unit molecular structure of lithium oxide.
Explanation:
Electronic configuration of lithium is :

In order to attain stable electronic configuration it will loose an electron and form positively charge cation.

The electronic configuration of oxygen is:

Oxygen being second most electronegative atom requires two electrons to attain noble gas configuration stability and form negatively charge ion with 2- charge.:

When two atom of lithium and oxygen comes together , one electron from each lithium atom get transferred to an oxygen atom which results in formation of lithium oxide.
