The correct answer is (B) Adding a dilute solution of HCl
<u>EXPLANATION</u>
The presence of carbonate ions can be tested by adding a dilute acid to the solution. The acid displaces Carbon (IV) oxide from the solution. Using HCl, and a carbonate of metal X.
XCO₃₍s₎ + 2HCl₍aq₎⇒ XCl₂₍aq₎+ H₂O₍l₎ + CO₂₍g₎
The gas produced is tested using calcium hydroxide to confirm whether it is carbon (IV) oxide.
It will become an ion and no longer be neutral
The atom's center, or nucleus, is positively charged and the electrons that whirl around this nucleus are negatively charged, so they attract each other. The reason the force is strong is because the atom is so small. The distance between the nucleus and the electrons is about 1 Angstrom (named after a famous scientist); this is 0.00000001 cm (10-8 cm) or about 4 billionths of an
<span>Let's assume
that the oxygen gas has ideal gas behavior.
Then we can use ideal gas formula,
PV = nRT</span>
Where, P is the pressure of the gas (Pa), V is the volume of the gas
(m³), n is the number of moles of gas (mol), R is the universal gas
constant ( 8.314 J mol⁻¹ K⁻¹) and T is temperature in Kelvin.
<span>
P = 2.2 atm = 222915 Pa
V = 21 L = 21 x 10</span>⁻³ m³
n = ?
R = 8.314 J mol⁻¹ K⁻¹
<span>
T = 87 °C = 360 K
By substitution,
</span>222915 Pa x 21 x 10⁻³ m³ = n x 8.314 J mol⁻¹ K⁻<span>¹ x 360 K
n
= 1.56</span><span> mol</span>
<span>
Hence, 1.56 moles of the oxygen gas are </span><span>
left for you to breath.</span><span>
</span>
