This is a simple chemical change due to what it produces and how it is added together. Hope this helps.
Answer:
42 19 K→42 20 Ca+e−
Explanation:
Naturally-occurring potassium atoms have a weighted average atomic mass of 39.10 (as seen on most modern versions of the periodic table.) Each potassium atom contains 19 protons p+ and thus an average potassium atom contains about 39.10−19≈20 neutrons n0.
This particular isotope of potassium-42 contains 42 nucleons (i.e., protons and neutrons, combined;) Like other isotopes of potassium 19 out of these nucleons are protons; the rest 42−19=23 are therefore neutrons.
Answer: Option (1) is the correct answer.
Explanation:
The molecular structure is as follows.
This compound contains carbon (C) atoms, hydrogen (H) atoms, oxygen (O) atoms.
Or, the chemical formula of this compound is 
.
Thus, we can conclude that there are five carbon atoms, eight hydrogen atoms and two oxygen atoms.
Answer:
Explanation:
The relation between frequency and wavelength is shown below as:
c is the speed of light having value 
Given, Wavelength = 515 nm
Also, 1 m = 
nm
So,
Wavelength = 
m
Thus, Frequency is:
Answer:
pH = 5.19
Explanation:
Mixture of acetic acid with sodium acetate produce a buffer (Buffer is defined as the mixture of a weak acid with its conjugate base and vice versa). The pH of the buffer can be determined using Henderson-Hasselbalch equation:
pH = pKa + log₁₀ [A⁻] / [HA]
<em>Where pKa is -log Ka = 4.75; [A⁻] is the concentration of conjugate base (Acetate ion) and [HA] is molar concentration of the weak acid.</em>
-You can use moles of the compounds rather than its concentrations, that is:
[HA] = 0.147 moles
[A⁻] = 0.405 moles
Replacing in H-H equation:
pH = 4.75 + log₁₀ [0.405] / [0.147]
<h3>pH = 5.19</h3>
