The vertical columns are groups
The horizontal rows are periods
Answer:
the mass of the glass is 2
Answer:
4.00 is the pH of the mixture
Explanation:
The ethyl amine reacts with HNO3 as follows:
C2H5NH2 + HNO3 → C2H5NH3⁺ + NO3⁻
To solve this question we need to find the moles of ethyl amine and the moles of HNO3:
<em>Moles C2H5NH2:</em>
0.0500L * (0.100mol/L) = 0.00500 moles ethyl amine
<em>Moles HNO3:</em>
0.201L * (0.025mol/L) = 0.005025 moles HNO3
That means HNO3 is in excess. The moles in excess are:
0.005025 moles HNO3 - 0.00500 moles ethyl amine =
2.5x10⁻⁵ moles HNO₃
In 50 + 201mL = 251mL = 0.251L:
2.5x10⁻⁵ moles HNO₃ / 0.251L = 9.96x10⁻⁵M = [H+]
As pH = -log [H+]
pH = -log 9.96x10⁻⁵M
pH = 4.00 is the pH of the mixture
Answer is (3) - ratio of neutrons to protons.
Isotopes are the atoms which have same atomic number but have different number of neutrons of same element.
Atomic nucleus can be stable or unstable. The stability of isotopes is based on neutron/ proton ratio. Unstable nucleus tries to become stable by emitting radiations.
Molar mass NaCl = 58 g
Mass of solute = 29 g
number of moles: mass of solute / molar mass
n = 29 / 58
n = 0.5 moles
hope this helps!
