The name of CH3CH2CH2CH2CH2CONH2 is: hexanamide butanamide pentanamide O heptanamide

What two conditions must satisfy to be called matter ?

prohojiy [21]

I can tell you one. Must have particles

6 0

3 years ago

Briefly describe bohr's model postulates and its limitations.

ch4aika [34]

Answer:

Bohr's Model postulates-

I postulate - The electrons in an atom orbit around the nucleus in definite circular paths called orbits or shells.

II Postulate - Each shell or orbit represents a specific amount of energy.

III Postulate - By emitting or absorbing energy, an electron may shift from one stationary energy orbit to another.

Three main Limitations -

1- It adjusts to the hydrogen atom's spectrum but not to the spectra of other atoms.

2 - In the definition of the electron as a tiny particle that spins around the atomic nucleus, the wave properties of the electron are not described.

3- Bohr is unable to understand why classical electromagnetism is inapplicable to his model. That is why, when electrons are in a stationary orbit, they do not emit electromagnetic radiation.

Explanation:

About Bohr's postulates-

1 - The electron spins in circling circles around the nucleus, emitting no energy. The orbital angular momentum is constant in these orbits.

Only certain radii of orbits, corresponding to certain given energy levels, are required for electrons in an atom.

2- Not every orbit is possible. However, whenever an electron is in a legal orbit, it is in a state of unique and constant energy and does not emit energy (stationary energy orbit).

For example - The energies allowed for electrons in the hydrogen atom are given by the following equation: The Rydberg constant for the hydrogen atom is $-2.8\times10^-^1^8$ in this equation, and n = quantum number will range from 1 to ∞. For each of the values of n, the electron energies of a hydrogen atom produced by the above equation are negative. As n rises, the energy becomes less negative and thus rises.

3- By emitting or absorbing energy, an electron may shift from one stationary energy orbit to another.

The energy difference between the two states would be equal to the energy released or consumed. This energy E is in the form of a photon, and it can be measured using the following formula:

$E=h$ $v$

E is the energy (absorbed or emitted) in this equation, and h is the Planck constant (its value is $6.63\times10^-^3^4 Js$ ) and v denotes the frequency of light, which is calculated in 1/ s.

8 0

2 years ago

1 - 2Na + O2 ➔ Na2O Balanced Not Balanced

Mrrafil [7]

Answer:

1 not

2 not

3 not

4 balanced

5 not

6 not

7 balanced

Explanation:

the amount of elements must be equal in the reactant and products

5 0

3 years ago

A 500 ml aqueous solution of na3po4 was prepared using 82g of the solute. what is the molarity

liraira [26]

Answer:

1 M

Explanation:

The molarity of a solution, M, is a measure of the concentration of that solution and it refers to the number of moles of solute (mol) per liter (L) of solution. The molarity (M) can be calculated using the formula:

M = number of moles (n) /volume (V)

In this question, a 500 ml aqueous solution of Na3PO4 was prepared using 82g of the solute.

Molar mass of Na3PO4 = 23(3) + 15 + 16(4)

= 69 + 31 + 64

= 164g/mol

Mole = mass/molar mass

mole = 82/164

mole = 0.5 mol

Volume in Litres (L) = 500 ml ÷ 1000 = 0.500L

Therefore, Molarity (M) = 0.5/0.500

Molarity = 1 M or 1 mol/L

7 0

3 years ago

The principal component of mothballs is naphthalene, a compound with a molecular mass of about 130 amu, containing only carbon a

DIA [1.3K]

Answer:

Empirical formula = C5H4

Molecular formula = C10H8

Explanation:

When the 3000 mg of naphthalene are burned they produce 10.3 mg of CO2. Knowing the unbalanced equation of the combustion of naphthalene, we have:

CxHy + O2 = CO2 + H2O

We calculate the molar composition of the sample. We look for the molecular weights in the periodic table:

CO2 = 12,011 + 2 (15,999) = 44,009 g

Mol C = 10.3 mg * (1 mol CO2 / 44.009 g CO2) * (1 mol C / 1 mol CO2) = 0.234 mmol C

Mass C = 0.234 mmol C * (12.011 g C / 1 mol C) = 2.8105 mg C

Mass H = 3 mg - 2.8105 mg = 0.1895 mg H

Mol H = 0.1895 mg H * (1 mol H / 1,008 g H) = 0.188 mmol H

To calculate the empirical formula, we must divide the number of moles of each element by the smallest number of moles, in this case, of hydrogen:

C = 0.2340 mmol C / 0.1895 mol H = 1.25

H = 0.1895 mmol H / 0.1895 mmol H = 1

We multiply the coefficients by 4, and we have the empirical formula:

C1.25 * 4H1 * 4 = C5H4

The molecular formula is equal to (C5H4)m, where m is calculated by the molecular and empirical mass ratio, as follows:

Empirical mass = (5 * 12.011) + (4 * 1.008) = 64.09 g

m = 130 g / 64.09 g = 2.02 = 2

Therefore we have the molecular formula:

(C5H4)2 = C10H8

4 0

3 years ago