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2 years ago

25. In the formula for a molecular compound, which atom generally comes first? You may went

Chemistry

1 answer:

vovikov84 [41]2 years ago

3 0

Answer:

For organic compounds, carbon and hydrogen are listed as the first elements in the molecular formula, and they are followed by the remaining elements in alphabetical order. For example, for butane, the molecular formula is C 4 H 10.

Explanation:

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What is the name of this hydrocarbon?

jenyasd209 [6]

Answer:

2-methylebutane

Explanation:

it is a hydrocarbon and there is a specific Rule for its nomenclature.

that is known as IUPAC naming system. According to it

The compound that has all single bonds name ends on ane.
Names according to the number of Carbons,

* For one carbon compound it is known as methane,

* For 2 ethane,

* For 3 propane

* For 4 Butane and so on.

select the longest chain of compound
Start numbering with lowest substituted position at carbon
branch compound name as Iso and neo as whole

So keeping in mind the compound can be named as

2-methylebutane

As the longest chain contain four carbon atoms so it will name as butane
The substitution of methyl group is on C-2

*Note: it can also named as isopantane as it is branched and have five carbons but it could not be 3-isopentane.

5 0

2 years ago

Read 2 more answers

E. The element 231/90Th decays to 231/91 Pa. Use the laws of conservation of charge and nucleon number to determine the decay pa

svetoff [14.1K]

Answer:

A negatron emission

Explanation:

We know that radioactivity orginates from instability of the nucleus. When the nucleus is unstable, radioactive emissions are produced in the form of any of these rays:

> Alpha particle emisson

>Beta particles

> Gamma rays

These emissions create a balance for a radioactive decay.

In balancing nuclear reactions we make sure that the charges on both sides must be conserved and that the mass number and atomic numbers conserved too. This means that the sum of mass number and atomic numbers on both side of the reaction must be equal.

The nucleons are the protons and neutrons, they add up to give the mass number. The atomic number is the proton number.

For the given radioactive reaction:

²³¹₉₀Th → ²³¹₉₁Pa + ?

From this equation, we see that the mass number is conserved but the atomic number is not.

The mass number is the superscript whereas the atomic number is the subscript.

Let's say the decay produces an emission of a particle denoted by X

²³¹₉₀Th → ²³¹₉₁Pa + ᵃₙX

What would the nature of X be?

For the charges and masses to be conserved, X must have mass number of 0 and an atomic number of -1.

Checking:

Mass number:

231 = 231 + a ( a is the mass number)

a = 231 - 231 = 0

Atomic number:

90 = 91 + n

n = 90- 91 = - 1

With X having a mass number of 0 and an atomic number of -1, we have a beta particle emission. Specifically, a negatron has been emitted.

A negatron is denoted as ⁰₋₁β which perfectly makes the equation conserved and suits the description of X.

The complete equation is thus written as:

²³¹₉₀Th → ²³¹₉₁Pa + ⁰₋₁β + energy

6 0

3 years ago

Why will a toy train remain still if you push on the engine with

netineya [11]

Explanation:

Because when two equal forces are applied from opposite directions, they "eliminate" each other.

The train would go right if a 3N force was only applied in the right direction, and it would go left if the same force was only applied to the left.

If a 3N force was applied to the right and a 2N force to the left, it would equal a 1N force to the right (3-2=1).

But there it's 3-3=0, so in practice the force is 0N. Therefore the train won't move.

6 0

2 years ago

NEED HELP FAST

andre [41]

Answer: im not writting a pharaphraph. Buuuuuuuuuuuut... explian the type of reaction then explanie how that type of reaction works.

Explanation:

6 0

2 years ago

Read 2 more answers

Calculate the moles of solute dissolved in 4.2 dm3 of a 0.5 mol / dm3 solution.

Archy [21]

Answer:

Example

0.5 mol of sodium hydroxide is dissolved in 2 dm3 of water. Calculate the concentration of the sodium hydroxide solution formed.

Concentration =

Concentration = 0.25 mol/dm3

Volume units

Volumes used in concentration calculations must be in dm3, not in cm3. It is useful to know that 1 dm3 = 1000 cm3. This means:

divide by 1000 to convert from cm3 to dm3

multiply by 1000 to convert from dm3 to cm3

For example, 250 cm3 is 0.25 dm3 (250 ÷ 1000). It is often easiest to convert from cm3 to dm3 before continuing with a concentration calculation.

Question

100 cm3 of dilute hydrochloric acid contains 0.02 mol of dissolved hydrogen chloride. Calculate the concentration of the acid in mol/dm3.

Reveal answer

Converting between units

The relative formula mass of the solute is used to convert between mol/dm3 and g/dm3:

to convert from mol/dm3 to g/dm3, multiply by the relative formula mass

to convert from g/dm3 to mol/dm3, divide by the relative formula mass

Remember: the molar mass is the Ar or Mr in grams per mol.

Example

Calculate the concentration of 0.1 mol/dm3 sodium hydroxide solution in g/dm3. (Mr of NaOH = 40)

Concentration = 0.1 × 40

= 4 g/dm3

8 0

3 years ago