You could ask whether the black crust is a new substance formed from silver underwent a chemical change because a chemical change produces a new substance.
Answer:
C
Explanation:
We know that the molar mass of KOH is 56 gmol-1
Molar mass of Mg(OH)2 is 58.31 g/mol
Now; the balanced reaction equation is; MgCl2 + 2KOH → Mg(OH)2 + 2KCI
Hence;
2 moles of KOH yields 1 mole of Mg(OH)2
4 moles of KOH yields;
4 moles of KOH/1 mol * 1 mole Mg(OH)2 /2 moles KOH * 58.31 g Mg(OH)2 / 1 mole Mg(OH)2
So option c is correct
Answer:
6.43 moles of NF₃.
Explanation:
The balanced equation for the reaction is given below:
N₂ + 3F₂ —> 2NF₃
From the balanced equation above,
3 moles of F₂ reacted to produce 2 moles of NF₃.
Finally, we shall determine the number of mole of nitrogen trifluoride (NF₃) produced by the reaction of 9.65 moles of Fluorine gas (F₂). This can be obtained as follow:
From the balanced equation above,
3 moles of F₂ reacted to produce 2 moles of NF₃.
Therefore, 9.65 moles of F₂ will react to to produce = (9.65 × 2)/3 = 6.43 moles of NF₃.
Thus, 6.43 moles of NF₃ were obtained from the reaction.
Answer:
The balloon becomes inflated
Explanation:
The equation of the reaction between baking soda (sodium bicarbonate) and vinegar(ethanoic acid) is shown below;
NaHCO3 + HC2CH3O2 ------> NaC2H3O2 + H2O + CO2
The gas (CO2) evolved in the process leads to the inflation of the balloon dropped on the bottle in which the reaction is taking pace.
This observation provides evidence that a gas was really evolved in the reaction.
i don't understand but atoms are made of electrons an protons and neutrons..