All categories

2 years ago

Which of the following statements is true?

1 answer:

3 0

The correct answer is C. Atoms are incredibly small and can bearly be seen with the most powerful electron microscopes. The nucleas of an atom contains protons and neutrons with electrons in orbitals around the nucleas. I hope this helps. Let me know if anything is unclear.

You might be interested in

HELP!!!!!

Crank

To get this it helps to know the electronegativity numbers of the elements but it isn't required. You just need to know that Fluorine is the most electronegative element and that the farther away from Fluorine you are on the periodic table, the less electronegative you get. The one exception to this rule is hydrogen with actually has an electronegativity of 2.1 while lithium has one of 1.0. Also the higher difference in electronegativity between two atoms the more polar the bond is.

Now to start the question. H-Br could be a contender since H has an electronegativity number of 2.1 and Br is relatively close to Fluorine so we'll put that one aside for now. H-Cl knocks out A because both bonds have H but one bond has Br and the other has Cl. Cl is closer to Fluorine than Br so answer B is the contender now. For answer C, I and Br are too close to have a higher electronegativity difference than H-Cl so that one isn't it. Finally for answer D, I is much closer to Cl than H is so the electronegativity difference is much less, making your answer B.

5 0

2 years ago

Be sure to answer all parts. What is the [H3O+] and the pH of a buffer that consists of 0.26 M HNO2 and 0.89 M KNO2? (K, of HNO2

Aleksandr-060686 [28]

Answer : The $H_3O^+$ ion concentration is, $1.12\times 10^{-3}M$ and the pH of a buffer is, 2.95

Explanation : Given,

$K_a=7.1\times 10^{-4}$

Concentration of $HNO_2$ (weak acid)= 0.26 M

Concentration of $KNO_2$ (conjugate base or salt)= 0.89 M

First we have to calculate the value of $pK_a$ .

The expression used for the calculation of $pK_a$ is,

$pK_a=-\log (K_a)$

Now put the value of $K_a$ in this expression, we get:

$pK_a=-\log (7.1\times 10^{-4})$

$pK_a=4-\log (7.1)$

$pK_a=3.15$

Now we have to calculate the pH of the solution.

Using Henderson Hesselbach equation :

$pH=pK_a+\log \frac{[Salt]}{[Acid]}$

$pH=pK_a+\log \frac{[KNO_2]}{[HNO_2]}$

Now put all the given values in this expression, we get:

$pH=3.15+\log (\frac{0.89}{0.26})$

$pH=2.95$

The pH of a buffer is, 2.95

Now we have to calculate the $H_3O^+$ ion concentration.

$pH=-\log [H_3O^+]$

$2.95=-\log [H_3O^+]$

$[H_3O^+]=1.12\times 10^{-3}M$

The $H_3O^+$ ion concentration is, $1.12\times 10^{-3}M$

4 0

2 years ago

Son el punto 2,3,4 por favor

RSB [31]

4...........................

8 0

3 years ago

Which is a balanced chemical equation?

Degger [83]

<h3>Answer:</h3>

B. C7H16 + 11O2 → 7CO2 + 8H2O

<h3>Explanation:</h3>

In a balanced chemical equation, the number of atoms of each element is equal on both sides of the equation.

In this case, the balanced chemical equation is;

C7H16 + 11O2 → 7CO2 + 8H2O

Because, it has 7 carbon atoms, 16 hydrogen atoms and 22 oxygen atoms on each side of the equation.

When an equation is balanced it obeys the law of conservation of mass such that the mass of reactants will be equal to the mass of products.

8 0

2 years ago

Which of the following statements about trends in solubility is accurate?

Kipish [7]

"The solubility of gases decreases as temperature rises" statements about trends in solubility is accurate.

<u>Option: D</u>

<u>Explanation:</u>

A substance's solubility is the quantity of that component that is needed at a defined degree of temperature to produce a saturated solution in any set quantity of solvent. Some compounds like hydrochloric acid, ammonia, etc have solubility that reduces with rising temperature. They are both standard-pressure gases.

When heating a solvent with a gas absorbed in it, both the solvent and the solute spike in the kinetic energy.When the gaseous solute's kinetic energy rises, the molecules have a higher propensity to overcome the solvent molecules' connection and migrate to the gas phase. Thus, a gas's solubility reduces with rising temperature.

4 0

3 years ago