Because they cannot survive long outside a living host cell.
Answer:
Calcium
Explanation:
Clacium has atomic number 20. The atomic number. This means that it has 20 protons and 20 electrons. it has 21 neutrons.
Answer:
pH = 5.76
Explanation:
We can solve this problem by using<em> Henderson-Hasselbach's equation</em>:
pH = pKa + log![\frac{[SodiumAcetate]}{[AceticAcid]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BSodiumAcetate%5D%7D%7B%5BAceticAcid%5D%7D)
We are already know all the required information, thus we<u> input the data given by the problem</u>:
pH = 4.76 + log(20/2)
And finally <u>calculate the pH</u>:
pH = 5.76
The pH of that acetic acid solution is 5.76.
Answer:

Explanation:
We are given the volumes and concentrations of two reactants, so this is a limiting reactant problem.
We know that we will need moles, so, lets assemble all the data in one place.
Cu²⁺ + 4NH₃ ⟶ Cu(NH₃)₄²⁺
V/mL: 3.00 7.00
c/mol·L⁻¹: 0.050 0.20
1. Identify the limiting reactant
(a) Calculate the moles of each reactant

(b) Calculate the moles of Cu(NH₃)₄²⁺ that can be formed from each reactant
(i) From Cu²⁺

(ii) From NH₃

NH₃ is the limiting reactant, because it forms fewer moles of the complex ion.
(c) Concentration of the complex ion
