Answer:
116.88 g
Explanation:
Step 1: Write the balanced equation for the synthesis of NaCl
Na + 1/2 Cl₂ ⇒ NaCl
Step 2: Calculate the moles corresponding to 45.978 g of Na
The molar mass of Na is 22.990 g/mol.
45.978 g × 1 mol/22.990 g = 1.9999 mol
Step 3: Calculate the number of moles of NaCl formed from 1.9999 moles of Na
The molar ratio of Na to NaCl is 1:1. The moles of NaCl formed are 1/1 × 1.9999 mol = 1.9999 mol.
Step 4: Calculate the mass corresponding to 1.9999 moles of NaCl
The molar mass of NaCl is 58.443 g/mol.
1.9999 mol × 58.443 g/mol = 116.88 g
Answer: A. Endothermic
Explanation:
In an endothermic reaction, heat is sucked in from the surrounding area by the reactants so that they may use it to react and form new products. This will therefore reduce the temperature in the said surrounding by the amount that the reaction needed.
This is what ice does when it melts. It sucks in the heat surrounding the area and then melts but leaves the area colder. For instance, putting ice in water ensures that the ice melts but because it sucked in the heat from the water to do so, the water gets colder as a result.
LiOH is soluble. Na2CO3 is soluble. Cu(OH)2 is insoluble.