Which number represetns a coefficient?
2
3
4
7
Which pair of elements would most likely have a similar arrangement of outer
electrons and have similar chemical behaviors?
boron and aluminum
helium and fluorine
carbon and nitrogen
chlorine and oxygen
Answer:
Boron and Aluminum
Explanation:
If you write the electron configuration for boron and aluminum, you get:
[tex]1s^22s^22p^1[/tex] for boron and [tex]1s^22s^22p^63s^23p^1[/tex] for aluminum. Both have 3 valance electrons and has 2 electrons in a s-orbital and 1 in a p-orbital. These valance electron similarities are based on the column/group the elements are. Therefore, Boron and Aluminum have similar chemical behaviours and similar arrangement of outer/valance electrons.
A baseball strikes the roof of a car and dents it. The paint on the roof begins to crack and chip, exposing the metal. The exposed metal on the roof rusts, eventually causing a small hole in the roof. 17. Which event is a chemical change? The baseball strikes the roof The roof of the car dents The paint cracks and chips The exposed metal rusts
Answer:
The exposed metal rusts is an example of a chemical change because rust is an example of a chemical change in objects for example bicycles, scooters, etc.
All of the following conditions in Earth can cause metamorphic rock to form EXCEPT
O pressure
O heat
the presence of hot, plastic like material
O exposure to air
Explanation:
heat
the presence of hot, plastic like material
Antoine Lavoisier correctly characterize as an element?
PLSSS HELP Match each image to the
correct step of meiosis. PLS HELP
Answer:
Explanation:
Here you go!! Hope this helps.
What are the two ways
that heat is measured?
Answer:
heat is mesured in calories and also joules
Explanation:
The pOH of an aqueous solution of 0.480 M trimethylamine (a weak base with the formula (CH3)3N) is .
Answer:
Explanation:
Kb of (CH₃)₃N is 7.4 x 10⁻⁵
initial concentration of (CH₃)₃N a is .48 M
(CH₃)₃N + H₂O = (CH₃)₃NH⁺ + OH⁻
a - x x x
x² / (a - x ) = Kb
x is far less than a so a - x can be replaced by a .
x² / a = Kb
x² = a x Kb = .48 x 7.4 x 10⁻⁵ = 3.55 x 10⁻⁵ = 35.5 x 10⁻⁶
x = 5.96 x 10⁻³
pOH = - log ( 5.96 x 10⁻³ )
= 3 - log 5.96
= 3 - .775
= 2.225
Ten moles of hydrogen are allowed to react with 6 moles of oxygen. How much water will be
obtained from reaction on complete consumption of one gas?
Answer:
10 moles of water are produced,
Explanation:
Given data:
Moles of H = 10 mol
Moles of O = 6 mol
Water obtained = ?
Solution:
Balance chemical equation:
2H₂ + O₂ → 2H₂O
Now we will compare the moles of H₂ and O₂ with water from balance chemical equation.
H₂ : H₂O
2 : 2
10 : 10
O₂ : H₂O
1 : 2
6 : 2×6 = 12
Number of moles of water produced by hydrogen are less so hydrogen will be limiting reactant and it will limit the yield of water thus, 10 moles of water are produced.
A student reacts 5.0 g of sodium with 10.0 g of chlorine and collect 5.24 g of sodium chloride. What is the percent yield of this combination reaction
Answer: The percent yield of this combination reaction is 41.3 %
Explanation : Given,
Mass of [tex]Na[/tex] = 5.0 g
Mass of [tex]Cl_2[/tex] = 10.0 g
Molar mass of [tex]Na[/tex] = 23 g/mol
Molar mass of [tex]Cl_2[/tex] = 71 g/mol
First we have to calculate the moles of [tex]Na[/tex] and [tex]Cl_2[/tex].
[tex]\text{Moles of }Na=\frac{\text{Given mass }Na}{\text{Molar mass }Na}[/tex]
[tex]\text{Moles of }Na=\frac{5.0g}{23g/mol}=0.217mol[/tex]
and,
[tex]\text{Moles of }Cl_2=\frac{\text{Given mass }Cl_2}{\text{Molar mass }Cl_2}[/tex]
[tex]\text{Moles of }Cl_2=\frac{10.0g}{71g/mol}=0.141mol[/tex]
Now we have to calculate the limiting and excess reagent.
The balanced chemical equation will be:
[tex]2Na+Cl_2\rightarrow 2NaCl[/tex]
From the balanced reaction we conclude that
As, 2 mole of [tex]Na[/tex] react with 1 mole of [tex]Cl_2[/tex]
So, 0.217 moles of [tex]Na[/tex] react with [tex]\frac{0.217}{2}=0.108[/tex] moles of [tex]Cl_2[/tex]
From this we conclude that, [tex]Cl_2[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]Na[/tex] is a limiting reagent and it limits the formation of product.
Now we have to calculate the moles of [tex]NaCl[/tex]
From the reaction, we conclude that
As, 2 mole of [tex]Na[/tex] react to give 2 mole of [tex]NaCl[/tex]
So, 0.217 mole of [tex]HCl[/tex] react to give 0.217 mole of [tex]NaCl[/tex]
Now we have to calculate the mass of [tex]NaCl[/tex]
[tex]\text{ Mass of }NaCl=\text{ Moles of }NaCl\times \text{ Molar mass of }NaCl[/tex]
Molar mass of [tex]NaCl[/tex] = 58.5 g/mole
[tex]\text{ Mass of }NaCl=(0.217moles)\times (58.5g/mole)=12.7g[/tex]
Now we have to calculate the percent yield of this reaction.
Percent yield = [tex]\frac{\text{Actual yield}}{\text{Theoretical yield}}\times 100[/tex]
Actual yield = 5.24 g
Theoretical yield = 12.7 g
Percent yield = [tex]\frac{5.24g}{12.7g}\times 100[/tex]
Percent yield = 41.3 %
Therefore, the percent yield of this combination reaction is 41.3 %
the moon lost its volcanic __ beacuse of its weak gravity
Answer:
Explanation:
the moon is still volcanic
Please help
What is an element
Answer:
An element is atoms with the same number of protons.
Explanation:
Protons, electrons, and neutrons.
How would you calculate an object's mechanical energy?
a. Add its kinetic and potential energies. b. Multiply its kinetic and potential energies.
c. Subtract its kinetic energy from its kinetic energy.
d. Subtract its potential energy from its kinetic energy.
Answer:
You would add its kinetic and potential energies.
Explanation:
Hope this helps!! :)
Answer:
A) Add its kinetic and potential energies
Explanation:
I got it right on Edge 2022
How many grams of MgSO4 should Naomi weigh out to prepare 0.250 L of a 1.25 M solution?
Answer:
Mass of MgSO₄ = 37.61 g
Explanation:
Given data:
Mass of MgSO₄ needed = ?
Volume of solution = 0.250 L
Molarity of solution = 1.25 M
Solution:
Formula;
Molarity = number of moles of solute / L of solution
Now we will put the values in formula:
1.25 M = number of moles of solute / 0.250 L
Number of moles of solute = 1.25 M ×0.250 L
(M = mol/L)
Number of moles of solute = 0.3125 mol
Mass = number of moles × molar mass
Mass = 0.3125 mol × 120.366 g/mol
Mass = 37.61 g
A 7.27-gram sample of a compound is dissolved in 250. grams of benzene. The freezing point of this solution is 1.02°C below that of pure benzene. What is the molar mass of this compound? (Note: Kf for benzene = 5.12°C/m.) Ignore significant figures for this problem. Group of answer choices 36.5 g/mol 146 g/mol 292 g/mol 5.79 g/mol 73.0 g/mol
Answer:
The correct answer is 146 g/mol
Explanation:
Freezing point depression is a colligative property related to the number of particles of solute dissolved in a solvent. It is given by:
ΔTf = Kf x m
Where ΔTf is the freezing point depression (in ºC), Kf is a constant for the solvent and m is the molality of solution. From the problem, we know the following data:
ΔTf = 1.02ºC
Kf = 5.12ºC/m
From this, we can calculate the molality:
m = ΔTf/Kf = 1.02ºC/(5.12ºC/m)= 0.199 m
The molality of a solution is defined as the moles of solute per kg of solvent. Thus, we can multiply the molality by the mass of solvent in kg (250 g= 0.25 kg) to obtain the moles of solute:
0.199 mol/kg benzene x 0.25 kg = 0.0498 moles solute
There are 0.0498 moles of solute dissolved in the solution. To calculate the molar mass of the solute, we divide the mass (7.27 g) into the moles:
molar mass = mass/mol = 7.27 g/(0.0498 mol) = 145.9 g/mol ≅ 146 g/mol
Therefore, the molar mass of the compound is 146 g/mol
13. (6C) An unknown chemical has the
following properties: it is a white crystal,
reacts with water, and has a high boiling
point. Which of these properties is
physical?
A White color only
B Reacts with water, high
boiling point
C Reacts with water only
D White color, high boiling
point
Answer: it is B
Explanation:
What is the reason behind an atom being neutral?
How many molecules are there in 985 mL of nitrogen at 0.0 degrees C and 1.00x10^-6 mm Hg?
(It would be better if work or steps to solve problem are given but if not its fine).
Answer:
3.48 x 1013 N2 molecules
step-by-step explanation:
Lets set up our equation first
P = 1.00 x 10-6 mm Hg T = 0.0° C + 273 = 273 K
We are given the V = 985 mL ,
R = 0.0821 L·atm/mol·K
Now use the ldeal gas law, but we are solving n, amount of substanvce
PV = nRT, we will change this equation to ;
n = PV/RT
n = 1.00 x 10-6 mm x 1 atm/760 mm x 985 mL x 1 L/103
mL/
(0.0821 L·atm/mol·K x 273 K) = 5.78 x 10-11 moles N2
nmolecules = 5.78 x 10-11 moles N2 x 6.02 x 1023 N2 molecules/1 mol N2
Suppose you are studying the kinetics of the iodine-catalyzed decomposition of hydrogen peroxide. 2 H 2 O 2 ⟶ 2 H 2 O + O 2 If you determine the initial rate is 7.50 × 10 − 4 M/s when [ H 2 O 2 ] = 0.546 M and [ K I ] = 0.212 M , what is the rate constant? Assume that the order of both reactants is 1.
Answer:
[tex]k=6.48x10^{-3}M^{-1}s^{-1}[/tex]
Explanation:
Hello.
In this case, based on the given information, we can write the rate law as shown below:
[tex]r=k[H_2O_2][KI][/tex]
Since the overall order of reaction is 2 being 1 for reach reactant. Thus, by knowing the initial rate and concentrations, the rate constant turns out:
[tex]k=\frac{r}{[H_2O_2][KI]}=\frac{7.50x10^{-4}M/s}{0.546M*0.212M}\\ \\k=6.48x10^{-3}M^{-1}s^{-1}[/tex]
Best regards!
The rate constant, k is [tex]6.48x10^{-3}M^{-1}s^{-1}[/tex]
Rate law:The rate law should be
[tex]r = k[H_2O_2]{KI}[/tex]
Since the total order of the reaction is 2 being 1 for reach reactant. So, by knowing the beginning rate and concentrations, the rate constant turns out:
[tex]k = \frac{r}{k[H_2O_2]{KI}} = \frac{7.50x10^{-4}M/s}{0.546M\times 0.212M}[/tex]
k = [tex]6.48x10^{-3}M^{-1}s^{-1}[/tex]
Learn more about reactants here; https://brainly.com/question/21029530
Atomic radius is....
O The tendency for an atom to attract electrons
The energy required to remove an electron
O The energy required to add an electron
O The distance from the nucleus to the last orbital
(5x10^3) + (4.3x10^4)=
Answer:
48000
Explanation:
maths
Answer:
48000
Explanation:
(5x10^3) = 5 × 1000 = 5000
(4.3x10^4) = 4.3 × 10000 = 43000
5000 + 43000 = 48000
how many moles are in a 4.2 gram gold sample
A 50.0 g sample of an unknown substance, initially at 20.2 °C, was heated with 1.55 kJ of energy. The final temperature of the substance was 125.0 °C. Determine the specific heat of this substance.
Answer:
0.296j/g⁰c
Explanation:
we have the following information from this question before us.
mass iv substance = 50grams
we have initial temperature ti = 20.2⁰c
final temperature = 125⁰c
the energy that was provided = 155kj
we proceed with this formula
energy = mcΔT
1.55x10³ = 50 x c x (125-20.2)
1.55x10³ = c x 50gm x 104.8k
we divide through to get c
c = 1.55x10³/50g x 104.8
c = 0.296J/g⁰c
that is the specific heat of this substance.
thank you!
HELP ME ASAP!
Under the Law of Multiple Proportions, Carbon Dioxide has a ratio of 2.666 g
Oxygen for every 1 g Carbon. Given this, how much oxygen is present in a sample
of carbon dioxide that has 16 g of carbon?
Answer:
In carbon dioxide, on the right, there is 2.666 g of oxygen for every gram of carbon. So the ratio of oxygen in the two compounds is 1:2, a small whole number ratio
please mark me as the brainliest answer and please please pleaseeee follow me.
8. Besides landforms, the other large features that cover the
surface of the earth are ______.
A. islands
B. waterways
C. deserts
D. lakes
Answer:
A landform is a feature on the Earth's surface that is part of the terrain. Mountains, hills, plateaus, and plains are the four major types of landforms. Minor landforms include buttes, canyons, valleys, and basins. Tectonic plate movement under the Earth can create landforms by pushing up mountains and hills.
Explanation:
"Waterways" are the other large features that cover the surface of the earth.
Waterways
A canal would be any body of water throughout which boats may move. Waterways, on the other hand, comprise waterways that seem to be expansive as well as shallow enough already to allow freight-carrying watercraft just to travel through.
Some bodies of water are usually regularly dredged to maintain an appropriately deep course throughout all circumstances. Dams change the depth of other rivers in particular parts.
Thus the response above i.e., "Option B" is correct.
Find out more information about landform here:
https://brainly.com/question/1920109
In chemistry, one often uses a unit of charge known as the Faraday, F, which has the magnitude of the charge of 1 mole of electrons. How many faradays of charge does that correspond to
Answer:
1 Faraday
Explanation:
This question seeks to test proper understanding of Faraday's second law of electrolysis which states when the same quantity electricity passes through a solution of different electrolytes, the mass of the substance deposited is directly proportional to there chemical equivalence.
This law hints at the charges of ions being the chemical equivalence and also been represented as the unit for the quantity of electricity in faraday, F. Hence, a metal with the charge of 1+ can be displaced by 1F (which is equal to 96, 500 coloumbs). This charge also represents one molecule of electron, thus 1 faraday corresponds to one mole of electrons.
NOTE: It should be noted that a metal with the charge of 2+ can be displaced by 2F and so on.
In which Earth system does the rock cycle take place?
cryosphere
atmosphere
geosphere
biosphere
Answer:
geosphere
Explanation:
geo means rocks this is the area
hope this helps dude
Explain how plucking occurs
Answer:
plucking is usually extracting hair
Explanation:
example: pluck the chicken feathers
pluck my brows
where in water is being converted into a gaseous form?
evaporation
condensation
transportation
precipitation
Answer:
It's called Evaporation.
An object accelerates 12.0 m / s ^ 2 when a force of 6.0 Newtons is applied to it what is the mass of the object
Answer:
The answer is 0.5 kgExplanation:
The mass of the object can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
where
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{6}{12} = \frac{1}{2} \\ [/tex]
We have the final answer as
0.5 kgHope this helps you
Answer:
The mass of object is 0.5 Kg.
Explanation:
Given data:
Acceleration of object = 12.0 m/s²
Force on object = 6.0 N
Mass of object = ?
Solution:
Formula:
F = m×a
F = force
m = mass
a = acceleration
Now we will put the values in formula.
6.0 N = m × 12.0 m/s²
m = 6.0 N / 12.0 m/s²
( N = kg.m/s²)
m = 0.5 kg
The mass of object is 0.5 Kg.