Which alcohol will behave most like water? C 10H 21OH C 2H 5OH C 7H 15OH C 4H 9OH

Which object would best be identified by a periodic Doppler shift in a star's spectrum along with a dip in the stars light inten

IgorLugansk [536]

The answer would be a planet<span>. Planets revolve around stars, which means there will come a point where the planet is between the star and our field of vision towards the star. This point will be where the star's radiation will have the lowest intensity. As the planet moves, the intensity will change. The effect is comparable to a lunar or solar eclipse.</span>

5 0

3 years ago

Select ALL correct answers. The contact force is caused by: A. Atoms randomly crashing into each other B. The charged particles

Inessa [10]

Answer:

A. Atoms randomly crashing into each other

E. The force of one object pushing against the force of another object.

Explanation:

Forces can be classified into two categories based upon the the mode of transfer or application:

1. Contact forces

2. Non-contact forces

Contact forces are the ones which require the physical contact of the matter to get transferred and tend to create the affect. Whereas non-contact forces have the field property which transfers the affect of force from one point to another without any physical contact of the matter or the medium.

Atoms crashing onto each other have some mass and velocity which upon collision impacts the other atoms exerts a contact force.
The interaction between the charged particles due to their charges is always due to the electric field be it electron or proton, be it within an atom or out of an atom.
The force between any two objects pushing or pulling each other is also possible only due to contact.

6 0

3 years ago

The reaction of NO2 with ozone produces NO3 in a second-order reaction overall.

Brilliant_brown [7]

Answer : The rate of reaction is,

$Rate=4.77\times 10^{-19}M/s$

The appearance of $NO_3$ is, $4.77\times 10^{-19}M/s$

Explanation :

The general rate of reaction is,

$aA+bB\rightarrow cC+dD$

Rate of reaction : It is defined as the change in the concentration of any one of the reactants or products per unit time.

The expression for rate of reaction will be :

$\text{Rate of disappearance of A}=-\frac{1}{a}\frac{d[A]}{dt}$

$\text{Rate of disappearance of B}=-\frac{1}{b}\frac{d[B]}{dt}$

$\text{Rate of formation of C}=+\frac{1}{c}\frac{d[C]}{dt}$

$\text{Rate of formation of D}=+\frac{1}{d}\frac{d[D]}{dt}$

$Rate=-\frac{1}{a}\frac{d[A]}{dt}=-\frac{1}{b}\frac{d[B]}{dt}=+\frac{1}{c}\frac{d[C]}{dt}=+\frac{1}{d}\frac{d[D]}{dt}$

From this we conclude that,

In the rate of reaction, A and B are the reactants and C and D are the products.

a, b, c and d are the stoichiometric coefficient of A, B, C and D respectively.

The negative sign along with the reactant terms is used simply to show that the concentration of the reactant is decreasing and positive sign along with the product terms is used simply to show that the concentration of the product is increasing.

The given rate of reaction is,

$NO_2(g)+O_3(g)\rightarrow NO_3(g)+O_2(g)$

The rate law expression will be:

$Rate=k[NO_2][O_3]$

Given:

Rate constant = $k=1.69\times 10^{-4}M^{-1}s^{-1}$

$[NO_2]$ = $1.77\times 10^{-8}M$

$[O_3]$ = $1.59\times 10^{-7}M$

$Rate=k[NO_2][O_3]$

$Rate=(1.69\times 10^{-4})\times (1.77\times 10^{-8})\times (1.59\times 10^{-7})$

$Rate=4.77\times 10^{-19}M/s$

The expression for rate of appearance of $NO_3$ :

$\text{Rate of reaction}=\text{Rate of appearance of }NO_3=+\frac{d[NO_3]}{dt}$

As, $\text{Rate of reaction}=4.77\times 10^{-19}M/s$

So, $\text{Rate of appearance of }NO_3=+\frac{d[NO_3]}{dt}=4.77\times 10^{-19}M/s$

Thus, the appearance of $NO_3$ is, $4.77\times 10^{-19}M/s$

7 0

3 years ago

Give the empirical formula for C↓8H↓8

mr_godi [17]

Answer:

Empirical formula of C₈H₈ = CH

Explanation:

Data Given:

Molecular Formula = C₈H₈

Empirical Formula = ?

Solution

Empirical Formula:

Empirical formula is the simplest ration of atoms in the molecule but not all numbers of atoms in a compound.

So,

tha ration of the molecular formula should be divided by whole number to get the simplest ratio of molecule

C₈H₈ Consist of Carbon (C), and Hydrogen (H)

Now

Look at the ratio of these two atoms in the compound

C : H

8 : 8

Divide the ratio by two to get simplest ratio

C : H

8/8 : 8/8

1 : 1

So for the empirical formula is the simplest ratio of carbon to hydrogen 1 : 1

So the empirical formula will be

Empirical formula of C₈H₈ = CH

4 0

3 years ago

Which of the following measurements is used to measure the enthalpy of combustion? A. None of these B. Measuring the change in t

DaniilM [7]

Answer: Option (C) is the correct answer.

Explanation:

In a substance, the total energy of its molecular motion is known as heat. Whereas when we measure the average energy of molecular motion of a substance then it is known as temperature.

So, any increase or decrease in temperature will lead to change in heat of a substance.

When one mole of a substance is burned then the amount of energy released in the form of heat is known as heat of combustion.

Relation between heat and temperature is as follows.

q = $m \times C \times \Delta T$

Thus, we can conclude that to measure the enthalpy of combustion it cannot be measured, only calculated using the equation; q = $mc \Delta T$ .

4 0

3 years ago