I didn't understand your question at first, I believe an acceptable answer would be As and Ar.
As (arsenic) is a metalloid and Ar (argon) is a noble gas.
Hopefully I was able to help you! :)
Answer:
a, d and e. are true.
Explanation:
The reaction that occurs is:
Na2CO3(aq) + CaCl2(aq) → CaCO3(s) + 2NaCl
In ideal conditions, the percent yield of the reaction must be 100%. All explanations about why the student could not collect all precipitate are right:
a. The combined reactants were not stirred before filtering the precipitate. Not stirring could not promote all the reaction. <em>TRUE.</em>
b. The student did not completely dry the precipitate before weighing it. If the student don't dry the precipitate, the mass of precipitate must be higher producing a percent yield > 100%. <em>FALSE.</em>
c. The precipitate was not washed prior to drying. Produce more mass. <em>FALSE.</em>
d. A rubber policeman was not used to scrape precipitate from the beaker. If the student doesn't collect all the precipitate the percent yield could be < 100%.. <em>TRUE.</em>
e. The filter paper was not wetted with water prior to filtering the precipitate. <em>TRUE. </em>If you don't wet the filter paper you can lose a part of precipitate from the walls of this one.
Answer:
epidemic
Explanation:
pandemic is much bigger and kill more people
Answer: Synthesis
0.84 moles of oxygen
25 moles of
Explanation:
The balanced chemical equation is:
This is a synthesis reaction as one product is formed by combination of two reactants.
According to stoichiometry :
a. 2 moles of require = 3 moles of
Thus 0.56 moles of require= of
b. 4 moles of give = 2 moles of
Thus 50 moles of give = of
Answer : The correct option is, (E) 6 moles.
Explanation : Given,
Moles of nitrogen = 2 moles
The given balanced chemical reaction is:
From the balanced chemical reaction we conclude that,
As, 1 mole of nitrogen gas react with 3 moles of hydrogen gas
So, 2 mole of nitrogen gas react with moles of hydrogen gas
Therefore, the number of moles of hydrogen gas needed to react with 2 moles of nitrogen gas is, 6 moles.