The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as system mass cannot change quantity if it is not added or removed. Hence, the quantity of mass is "conserved" over time.
Answer:
2.453.
Explanation:
<em>∵ pH = - log[H₃O⁺]
</em>
[H₃O⁺] = 0.00352 M.
<em>∴ pH = - log[H₃O⁺] </em>= - log(0.00352) = <em>2.453.</em>
Answer:
Relative atomic mass and it is expressed in atomic mass unit (amu)
Explanation:
AMU:
Atomic mass unit is define as the 1/12 the mass of an atom of carbon-12.
C12 has six neutron and six protons in the nucleus.
This unit is used to express the masses of atoms. We know that masses of atoms are very small and we do not have any such type of balance that can measure very small quantity. So that is way we use this scale to measure small quantity. For example, according to this scale
relative atomic mass of hydrogen is 1.008 amu
relative atomic mass of oxygen is 15.999 amu
relative atomic mass of uranium is 238.0289 amu
relative atomic mass of chlorine is 35.453 amu
Molar mass:
KCl = 74.55 g/mol
KClO3 = 122. 55 g/mol
<span>Calculation of the mass of KClO3 :</span>
<span>2 KClO3 = 2 KCl + 3 O2</span>
2* 122.55 g KClO3 ------------------ 2 * 74.55 g KCl
mass KClO3 ?? --------------------- 25.6 g KCl
mass KClO3 = 25.6 * 2 * 122.55 / 2 * 74.55
mass KClO3 = 6274.56 / 149.1
mass = 42.082 g of KClO3
Therefore:
1 mole KClO3 ---------------------- 122.55 g
?? moles KClO3 ------------------- 42.082 g
moles KClO3 = 42.082 * 1 / 122.55
moles KClO3 = 42.082 / 122.55
=> 0.343 moles of KClO3
Answer C
hope this helps!
