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3 years ago

About 10-15% of all galaxies are which shape?

Chemistry

2 answers:

PSYCHO15rus [73]3 years ago

7 0

The answer is Irregular.

Anestetic [448]3 years ago

4 0

Your awnser would be B

You might be interested in

At equilibrium, no chemical reactions take place. true or false

arsen [322]

False. At equilibrium, the rate of forward reaction is equal to the rate of backward reaction. The net concentration of both products and reactants won't change, but the reactions still take place.

6 0

3 years ago

An unknown acid was titrated two times with 0.10 M NaOH. The first titration was done using an indicator to determine the equiva

Anit [1.1K]

Answer:

hello your question is incomplete attached below is the complete question

a) 0.12 M

b) Ka = 3.0 * 10^-7

c) Alizarin Yellow R

Explanation:

<u>A) Determine the concentration of the unknown acid</u>

The PH of the unknown acid before addition of NaOH is ; 3.72 ( weak acid )

First determine the moles of of NaOH

= molarity * volume

= 0.10 M * 30.0 ML = 0.0030 mol

at equivalence point

moles of NaOH = moles of unknown acid = 0.0030 mol

volume of unknown acid = 25.0 mL

Next calculate the concentration of the Acid ( HA )

= moles / volume

= 0.0030 mol / 25.0 mL

= 0.12 M

<u>b) Determine the Ka of the unknown acid </u>

attached below is the detailed solution

Ka = 3.0 * 10^-7

c) The indicator that would be a good choice to use in the titration of this acid with NaOH is ; Alizarin Yellow R . this is because the titration is between a strong base and a weak acid.

7 0

3 years ago

1. How many moles of carbon are in 2.25 * 10^22 atoms of carbon ?

tresset_1 [31]

Answer:

atoms of C? 2.25 x 1022 atoms C x 1 mole C = 0.037 mol C

Explanation:

How many moles of C are in 2.25 x 1022 atoms of C?

3 0

3 years ago

On a mission to a newly discovered planet, an astronaut finds chlorine abundances of 13.85 % for 35Cl and 86.15 % for 37Cl. What

topjm [15]

Answer : The atomic mass of chlorine is, 36.723 amu

Explanation :

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$

As we are given that,

Mass of 35-Cl isotope = 35 amu

Percentage abundance of 35-Cl isotope = 13.85 %

Fractional abundance of 35-Cl isotope = 0.1385

Mass of 37-Cl isotope = 37 amu

Percentage abundance of 37-Cl isotope = 86.15 %

Fractional abundance of 37-Cl isotope = 0.8615

Now put all the given values in above formula, we get:

$\text{Average atomic mass }=[(35\times 0.1385)+(37\times 0.8615)]$

$\text{Average atomic mass }=36.723amu$

Therefore, the atomic mass of chlorine is, 36.723 amu

6 0

4 years ago

BRAINLIESTTT ASAP!! PLEASE HELP ME ASAP!

Alexandra [31]

Answer:

Single displacement and reduction

Explanation:

In a single-displacement reaction, one element exchanges partners with another.

$\rm Ca + 2H$_2$O $\longrightarrow$ Ca(OH)$_2$ + H$_2$$

This is a single-displacement reaction, because the element Ca exchanges partners with H.

This is also a reduction/oxidation (redox) reaction, because the optically active of Ca increases from 0 to +2 (oxidation), while the oxidation number of H decreases from +1 to 0 (reduction),

The most common types of reactions are:

Combination
Decomposition
Single displacement
Double displacement
Reduction/oxidation

4 0

3 years ago