What does the VSEPR theory predict?
A. The chemical formula of a molecule
B. The size of a molecule
C. The shape of a molecule
D. The charge of a molecule
Answer: C
Explanation:
A P E X
The VSEPR theory predicts the shape and molecular geometry of the molecule.
What is molecular geometry?Molecular geometry can be defined as a three -dimensional arrangement of atoms which constitute the molecule.It includes parameters like bond length,bond angle and torsional angles.
It influences many properties of molecules like reactivity,polarity color,magnetism .The molecular geometry can be determined by various spectroscopic methods and diffraction methods , some of which are infrared,microwave and Raman spectroscopy.
They provide information about geometry by taking into considerations the vibrational and rotational absorbance of a substance.Neutron and electron diffraction techniques provide information about the distance between nuclei and electron density.
Learn more about molecular geometry,here:
https://brainly.com/question/28557524
#SPJ2
1.Mitch weighs out 67 grams of potassium (K) to make a buffer. How many moles of potassium did Dr. Hellman weigh out?
2.Which statement is NOT true about a reaction rate?
Group of answer choices
Increases with increase in reactant concentration
Increases with increasing temperature
Is the speed at which product is formed
Is the rate at which reactant is used up
All of the answers are true
3.Which statement is NOT true about a catalyst?
Group of answer choices
Are not used up during a reaction
Increases the rate of the reaction
Lowers the energy of activation
Biological catalysts are called enzymes
Are used up during a reaction
Answer:
1. 1.72 moles of potassium.
2. All of the answers are true
3. Are used up during a reaction
Explanation:
Recall that the number of moles is obtained from;
Number of moles= Mass of potassium/ molar mass of potassium
Mass of potassium= 67 g
Molar mass of potassium= 39 gmol-1
Number of moles of K= 67 g/ 39 gmol-1
Number of moles = 1.72 moles of potassium.
2. When we look at all the options, we will realize that all the options are true. The rate of reaction doubles for each 10°C rise in temperature, increasing reactant concentration increases particle collision and ultimately increases the rate of reaction. Rate of reaction deals with rate of disappearance of reactants or rate of appearance of products.
3. Catalysts remain unchanged in a chemical reaction because they do not actually participate in the reaction. Hence they are not used up in any chemical reaction.
When naming acids, the term “hydro” is used then there are or are not (pick the correct one) any oxygens.
Answer:
There are no oxygen
Explanation:
Hydro is used when naming hydrogen compound and oxo is used when naming oxygen compound
the force that keeps the nucleons bound inside the nucleus of an atom
Answer:
Strong Nuclear Force
Explanation:
Strong Nuclear Force; is the force that keeps the nucleons bound inside the nucleus of an atom. It is a short range attractive force that acts between all nucleons in the nucleus of the atom that is much stronger than electrical forces.
Answer:
nuclear force
Explanation:
a. 24.5 g of ammonia NH3 = how many moles of ammonia?
.b How many molecules of ammonia is that from 22.a.?
A balloon containing helium gas expands from 230 mL to 860 mL as more helium is added. What was the initial quantity of helium present if the expanded balloon contains 3.8 × 10-4 mol, assuming constant temperature and pressure? Which of the variables are known?
Answer and Explanation:
For computing the initial quantity of helium we have to apply the law of ideal gas which is shown below:
[tex]pV=nRT\[/tex]
[tex]n=\dfrac{pV}{RT}[/tex]
Now we have to compute the ratio between the initial and the final numbers of moles which is
[tex]\dfrac{n_1}{n_2}=\dfrac{\dfrac{p_1V_1}{RT_1}}{\dfrac{p_2V_2}{RT_2}}[/tex]
The statement defines that
[tex]T_1=T_2,~p_1=p_2.[/tex]
Therefore
[tex]\dfrac{n_1}{n_2}=\dfrac{V_1}{V_2}[/tex]
[tex]\dfrac{n_1}{3.8\times10^{-4}}=\dfrac{230}{860}\iff\\\\ n_1=\dfrac{3.8\times10^{-4}\times230}{860}[/tex]
[tex]\boxed{n_1\approx1.0\times10^{-4}~mol}[/tex]
And, the variables are known is starting volume and ending gas quantity
Answer:
beginning volume and ending quantity of gas
Explanation:
Napisz równania reakcji chemicznych w formie cząsteczkowej, jonowej i jonowej skróconej. Podkreśl wzory soli trudno rozpuszczalnych i podaj ich nazwy.
palmitynian potasu + chlorek magnezu
zapis cząsteczkowy reakcji...………………..
zapis jonowy...…………………….
zapis jonowy skrócony...……………….
nazwa soli trudno rozpuszczalnej...……………..
oleinian sodu + azotan (V) wapnia
zapis cząsteczkowy reakcji...………………..
zapis jonowy...…………………….
zapis jonowy skrócony...……………….
nazwa soli trudno rozpuszczalnej...……………..
Answer:idioma equivocado ????
Explanation:
If the temperature outside is 297 what is this temperature in degrees celsius
Answer:
147.222 degrees C
Explanation:
assuming its 297 F it should be correct
The temperature outside is 297°F then this temperature in celsius is equal to 147.22 °C.
How to convert from Fahrenheit to celsius?Temperature can be described as a physical quantity that expresses quantitatively the perceptions of hotness or coldness. The most general scales are the Celsius scale with (°C), the Fahrenheit scale (°F), and the Kelvin scale (K), the latter being used predominantly for scientific purposes.
Fahrenheit to Celsius formula can be used to change the temperature from the scale Fahrenheit to degrees Celsius.
The formula that can be used to convert Fahrenheit to Celsius is given below:
[tex]\dusplaystyle ^oC = (^oF - 32) \times \frac{5}{9}[/tex]
Here, F represents the temperature in Fahrenheit, and C represents the temperature in Celsius.
Given the temperature in Fahrenheit = 297 °F
[tex]\dusplaystyle T( ^oC) = (297 - 32) \times \frac{5}{9}[/tex]
T = 147.22 °C
Therefore, the given temperature in celsius is equal to 147.22 °C.
Learn more about temperature, here:
https://brainly.com/question/14453171
#SPJ2
Someone please help me!!
Answer:
the 3rd one (0.01 cm the one selected already)
Explanation:
copper wire isn't excessively big, and it wraps around the pencil because its malleable. I think that the most accurate would be 0.01 cm
When KCl dissolves in water
Answer:
They form K₂O (Potassium oxide) and HCl (Hydrochloric acid). This is because K and H are positively charged and O and Cl are negatively charged and cations only bond with anions.
In an ecosystem, why can only one species fill an ecological niche?
Answer:
Explanation:es porque las especies con nichos idénticos tienen las mismas necesidades, lo que significa que competirían exactamente por los mismos recursos.
What is the answer to this ?
Answer:
12.78 or 12.80 mostly like 12.78
Explanation:
We know from the relative amounts of 16O and 18O that global temperatures and global climate have changed over time. Why is it important for scientists to be able to explain how they know that climate has changed over time and that they are able to repeat experiments that support this information?
Answer:
In order to take steps by humans for controlling the change in climate.
Explanation:
It is important that scientist find out the change which occurs in the climate with the passage of time by performing experiments and also repeat the experiments in order to verify their findings. Due to these experiments, scientists also find out the reasons behind of climate change which enable us to take steps in preventing the change that occurs in the environment. it is also important for scientists to be able to explain how they know that climate has changed over time in order to explain that he is not assuming or making predictions, he has to provide evidence for his statement which is only be possible through experiments.
NEED HELP
What is the temperature in kelvin of a gas if it is allowed to expand from 1.50 L to 4.50 L? The initial temperature is 10.0°C and pressure is constant throughout the change. Which equation should you use?
Answer:
Explanation:
V1/T1 =V2/T2 at constnant pressure
Answer:
c
Explanation:
Which group is in the leftmost column on the periodic table?
alkali metals
a.pex
yes
The graph below shows how the temperature and volume of a gas vary when the number of moles and the pressure of the gas are held constant. How can the volume of the gas be increased if the pressure is constant?
Answer:
Option C. By increasing the temperature
Explanation:
From the graphical illustration above, we see clearly that the volume and temperature of the gas are directly proportional. This implies that as the temperature increases, the volume will also increase and as the temperature decreases, the volume will also decrease. This can further be explained by using the ideal gas equation as shown below:
PV = nRT
P is the pressure.
V is the volume.
n is the number of mole.
R is the gas constant.
T is the temperature.
PV = nRT
Divide both side by P
V = nRT/P
Since n and P are constant, the equation above becomes:
V & T
V = KT
K is the constant.
The above equation i.e V = KT implies that:
As T increases, V will also increase and as T decreases, V will also decrease.
Considering the question given above,
The volume of the gas can be increased if the temperature is increased.
QUESTION 20 Which of the following is a producer? oak tree raccoon cockroach human
Answer:
may be the first one is a producer
What does the pH of a solution measure?
O A. Color
O B. Volume
O c. Temperature
O D. Acidity
Answer:
D is the correct answer acidity
Explanation:
pH is the logarithmic measurement of the H3O+-concentration in water solutions.
By definition: pH = -log[H3O+]
Example: [H3O+] = 1.0*10-7 mol/L in neutral, pure water (at 25oC), so
pH = -log(H3O+) = -log(1.0*10-7) = 7.0
The nickname __________ was given to people from southern states that supported reconstruction laws that helped African Americans.
A. "copperhead"
B. "scalawag"
C. "carpetbagger"
D. "Radical Republican"
Which of these is NOT an example of how your community uses natural
resources?
If a 200 g piece of aluminum has a density of 5.0 g/cm^3. what is its volume?
Answer:
Volume=mass in g /density
Answer: 40cm^3 or 40ml
Explanation:
[tex]Density=\frac{mass}{volume}[/tex]
so 5=200/V
V=200/5
V=40cm^3
The table below shows the similarity of Methane and water in molecular mass. They are also similar in both size and shape. Why does Methane exist in the gas state with a very low boiling point?
Answer:
Explanation:
In case of Water there are strong hydrogen boding excist as result shows high boiling point, wher as in case of methane the there is no hydrogen bond and excist weak vanderwall attraction between the molcuels so the lower boiling point.
Which material is most likely to be a base?
salt water
vinegar
coffee
orange juice
Answer:
Cooffee
Explanation:
the answer is coffee because coffee might be bitter
Answer:Coffee
Explanation:Water is neutral, while the other answers are mostly organic acids but salt water is neither acidic nor basic
what is freshly prepared FeSO4 used in the brown ring test
Answer:
Freshly prepared ferrous sulphate is used in brown ring test, because if FeSO4 is stored or it is the old one then it reacts with atmospheric oxygen and gets oxidized to form a corrosive brown-yellow coating of basic ferric sulphate, which is an adduct of ferric oxide and ferric sulphate
HEYA FRIEND
.
.
HERE'S YOUR ANSWER
.
.
.
.
It is used in brown ring test because , if Fe2So4 is stored or it is old one then it reacts with atmospheric oxygen and gets oxidized to form a corrosive brown yellow coating of basic ferric sulphate , which is an adduct of ferric oxide and ferric sulphate.
.
✌✌✌
HOPE IT WILL HELP YOU UP
.
.
KATË
Level 3- How is tooth decay related to pH?How can it be prevented?
Answer:
A lower pH of the mouth creates bad bacteria that eventually lead to decay of the tooth.
It can be prevented by avoiding food that causes acidity.
Explanation:
Tooth decay is caused by the pH level in the mouth dropping below 5.5, meaning it is acidic. It can be prevented by brushing your teeth as toothpaste is an alkali which will neutralise the pH level in your mouth.
Hope this helps
what is chemistry?
Answer:the branch of science which examines the material of the universe and changes that these materials undergo
Chemistry deals with composition,structure,properties of matter and changes that these materials undergo
Which equation represents fermentation? 1. C2H4 + H2O → CH3CH2OH 2. C2H4 + HCl → CH3CH2Cl 3. C6H12O6 → 2CH3CH2OH + 2CO2 4. 2CH3CHO → C3H5CHO + H2O
Answer:
3. C6H12O6 → 2CH3CH2OH + 2CO2
Explanation:
In fermentation a catabolic process occurs, where an organic substance (C6H12O6) is transformed into a simpler one (CH3CH2OH), through incomplete oxidation, which does not require oxygen. Sugars are transformed into ethyl alcohol and carbon dioxide.
The equation C₆H₁₂O₆ → 2CH₃CH₂OH + 2CO₂ represents fermentation
What is Fermentation ?Fermentation is an enzyme catalyzed, metabolic process whereby organisms convert starch or sugar to alcohol or an acid anaerobically releasing energy.
In this process a large molecule is broken down to a smaller molecule.
Among the Equations given Equation 3
C₆H₁₂O₆ → 2CH₃CH₂OH + 2CO₂
represents fermentation due to two reasons
It is the process of breaking down of SugarIt is breaking down of a large molecule into smaller molecules.To know more about Fermentation
https://brainly.com/question/13050729
#SPJ5
Give some examples of how ultraviolet rays can be used
Answer:
One of the most common ways of producing UV light is passing an electric current through vaporized mercury or some other gas. This type of lamp is commonly used in tanning booths and for disinfecting surfaces. The lamps are also used in black lights that cause fluorescent paints and dyes to glow.Explanation:
How many moles of gas are contained in a 60.0L cylinder at a pressure of 200.0 atm and a temperature of 25.0? A.(490.48 mol) B.(590.84 mol) C.(340.56 mol) D.(540.67 mol)
Answer: A. 490.48mol
Explanation:
Using the ideal gas equation; PV =nRT
where P = Presssure = 200 atm
V = Volume = 60L
n = Number of moles
R = Gas constant = 0.08206 L.atm/mol/K
T = Temperature = 25 °C + 273 = 298K
Make "n" the subject of the formular;
n = PV / RT
= 200 x 60 / 0.08206 x 298
= 490.73 mol, which is closest to option A. 490.48mol
before the digestive system X-rayed people are required to swallow suspensions of barium sulphate (BaSO4). calculate the mass of one mole of BaSO4
Answer:
Molar mass of BaSO4 = 137.3 + 32 + (16 ×4)
= 137.3 + 32 +64
= 233.3g/mol
Molar mass = mass/ number of moles
= 233.3 g/mol = mass/ 1 mol
mass = 233.3g
Hope this helps.