Answer:
The fourth one down
Explanation:
It is the only setup in which the units of "cm" and "in" cancel correctly and give the desired units of "ft."
The second one down has the correct units but the wrong conversion factor for converting centimetres to inches.
Answer: An initial velocity
Explanation:
Answer:
165 of CO₂.
Explanation:
In the reaction:
Na2CO3 + 2HCl → 2NaCl + CO2 + H2O
2 moles of HCl reacts producing 1 mole o CO₂
If 7.5 moles of HCl reacts, moles of CO₂ produced are:
7.5 moles of HCl ₓ ( 1 mol CO₂ / 2 mol HCl) = 3.75 mol CO₂. As molar mass of CO₂ is 44g/mol, mass of CO₂ is:
3.75 mol CO₂ ₓ (44g / 1mol) = <em>165 of CO₂ </em>
The molar mass is 242 g/mol (<span>241.8597 g/mol). There is a very good online service to calculate molar masses:
http://www.webqc.org/mmcalc.php
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X is the answer that we do not know yet!!:)
