Answer : A nucleotide is composed of a phosphate group and a nitrogen-containing base.
Explanation :
Nucleotide : It is a building block of nucleic acids or we can say that it is building block of DNA and RNA.
It is composed of three sub-unit molecules which are a nitrogenous base, a five-carbon sugar and one phosphate group.
Nucleotide forms covalent bonds with other nucleotide for the formation of the nucleic acid strand.
Hence, a nucleotide is composed of a phosphate group and a nitrogen-containing base.
D = M/V
D = 0.10
V = 1000 cm^3
0.10 = M / 1000
M = 100
Porque la densidad es 10%, se puede usar 0.10 en este formulario para calcular el peso. No sé lo que es la unidad para el peso pero es 100.
Answer:
The atomic mass of gallium (Ga) = <u>69.723 g/mol</u>
Explanation:
Given: Two isotopes of Gallium (Ga) are Gallium-69 (⁶⁹Ga) and Gallium-71 (⁷¹Ga)
<u>For ⁶⁹Ga: </u>
Relative abundance = 60.12% = 60.12 ÷ 100 = 0.6012; Atomic mass = 68.9257 g/mol
<u>For ⁷¹Ga:</u>
Relative abundance = 39.88% = 39.88 ÷ 100 = 0.3988; Atomic mass = 70.9249 g/mol
∴ The atomic mass of Ga = (Relative abundance of ⁶⁹Ga × Atomic mass of ⁶⁹Ga) + (Relative abundance of ⁷¹Ga × Atomic mass of ⁷¹Ga)
⇒ Atomic mass of Ga = (0.6012 × 68.9257 g/mol) + (0.3988 × 70.9249 g/mol) = <u>69.723 g/mol</u>
<u>Therefore, the atomic mass of gallium (Ga) = 69.723 g/mol</u>
Answer:
1.58x10⁻⁵
2.51x10⁻⁸
0.0126
63.10
Explanation:
Phenolphthalein acts like a weak acid, so in aqueous solution, it has an acid form HIn, and the conjugate base In-, and the pH of it can be calculated by the Handerson-Halsebach equation:
pH = pKa + log[In-]/[HIn]
pKa = -logKa, and Ka is the equilibrium constant of the dissociation of the acid. [X] is the concentrantion of X. Thus,
i) pH = 4.9
4.9 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = - 4.8
[In-]/[HIn] = 
[In-]/[HIn] = 1.58x10⁻⁵
ii) pH = 2.1
2.1 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -7.6
[In-]/[HIn] = 
[In-]/[HIn] = 2.51x10⁻⁸
iii) pH = 7.8
7.8 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -1.9
[In-]/[HIn] = 
[In-]/[HIn] = 0.0126
iv) pH = 11.5
11.5 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = 1.8
[In-]/[HIn] = 
[In-]/[HIn] = 63.10
<u>Answer:</u> The product side must be 
<u>Explanation:</u>
Single displacement reaction is defined as the reaction in which more reactive metal displaces a less reactive metal from its chemical reaction.

Metal C is more reactive than metal A.
The reactivity of metal is determined by a series known as reactivity series. The metals lying above in the series are more reactive than the metals which lie below in the series.
Law of conservation of mass states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form. This also means that total number of individual atoms on reactant side must be equal to the total number of individual atoms on the product side.
When zinc metal reacts with hydrochloric acid, it leads to the production of zinc chloride and hydrogen gas. The chemical reaction follows:

<u>On reactant side:</u>
Number of zinc atoms = 1
Number of hydrogen atoms = 2
Number of chlorine atoms = 2
<u>On product side:</u>
Number of zinc atoms = 1
Number of hydrogen atoms = 2
Number of chlorine atoms = 2
Hence, the product side must be 