Do particles in air take the space of the container when some particles of air are released?

A 25.0 mL sample of 0.100 M lactic acid (HC3H503, Ka = 1.4 E-4) is titrated with 0.100 M NaOH solution. Calculate the pH of the

aleksklad [387]

I’m a bit confused too

4 0

3 years ago

If 2.60 g of NaBr are dissolved in enough water to make 160. mL of solution, what is the molar concentration of

navik [9.2K]

This problem has two parts; the first one asking for the concentration of NaBr given both its mass and volume and the second one asking for its volume given both mass and concentration. The answers turn out to be 0.158 M and 211 mL.

<h3>Molarity</h3>

In chemistry, the use of units of concentration depends on both the substances to analyze and their amounts. In such a way, for molarity, one needs the following relationship between the moles of solute and volume of solution:

$M=\frac{n}{V}$

Thus, for the first part of the problem we first calculate the moles in 2.60 g of NaBr via its molar mass:

$2.60g*\frac{1mol}{102.89g} =0.0253mol$

Next, we convert the 160. mL to L by dividing by 1000 in order to obtain 0.160 L to subsequently calculate the molarity:

$M=\frac{0.0253mol}{0.160L}=0.158M$

Next, since the moles remain the same and for the second part we are asked for the volume given the concentration, one can solve for the volume so as to obtain:

$V=\frac{n}{M} =\frac{0.158M}{0.120mol/L}\\ \\V=0.211L$

That in milliliters turns out to be:

$V=0.211L*\frac{1000mL}{1L}=211mL$

Learn more about molarity: brainly.com/question/10053901

6 0

1 year ago

Write the balanced chemical equation for the following: The destruction of a marble statuary by acid rain: aqueous nitric acid r

Mashcka [7]

Answer: The coefficient in front of nitric acid is 2

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas. Liquids are represented by (l) and gases are represented by (g).

The balanced chemical reaction is :

$CaCO_3(s)+2HNO_3(aq)\rightarrow Ca(NO_3)_2(aq)+CO_2(g)+H_2O(l)$

7 0

2 years ago

Give two examples of steroids

Sonbull [250]

Steroids are like hormones that greatly influences bodily activities mostly in growth and function. These functions may modify, change and control one’s body organs or system that’ll vary in form, shape or structure due to these hormone-like compounds and also, it can affect one’s psychological and neurological state. There are several types of steroids. Examples can include: 
1. Sex steroids. These are can influence reproduction and sex characteristics. 
2. Anabolic steroids. Most abused in many athletic activities. These steroids are used for muscle and bone growth.

3 0

2 years ago

when a number in scientific notation contains a significant zero, is that zero also significant in the expanded notation? give t

AlexFokin [52]

I believe you are referring zero as the exponent. Any number (except 0) with exponent 0 is defined to mean 1.

For one thing, there is a rule:

a^m/ a^m = a^m-m = a^0

But (when a is not equal to 0),

a^m/ a^m = 1

Therefore, we must define a^0 as 1.

4 0

3 years ago