Answer:
F-
Explanation:
The atomic radius of F is 72 pm and that of F- is 136 pm.
I REALLY NEED HELP can someone help me please I’ll make you brainliest ! :)
Answer:
C
Explanation:
All thing in option c is flammable
Answer:
D
Explanation:
Which of the following is an example of a physical change?
A. Getting a suntan
B. Digesting your food
C. Cutting your hair
D. Growing taller
SUBMIT
Answer:
C. Cutting your hair
Explanation:
A physical change is one of the two types of changes in nature (the other being chemical change). A physical change does not affect the chemical composition of the substance(s) involved.
In this case, "CUTTING ONE'S HAIR" is an example of physical change because it involves the removal of the hair without altering the chemical composition of the hair. However, other examples given in the options of this question like digestion of food, getting a suntan (change in skin coloration), and growth in height all involve a change in the chemical nature of the parts involved, hence, they are examples of chemical changes.
Can some one help me plz
Answer:
what does it say its blurry
Explanation:
Question 11 of 31
What is the molarity of 820 mL of Kl solution that contains 36.52 g of KI?
The Periodic Table
A. 45 mol/L
B. 0.27 mol/L
C. 2.7 x 10-4 mol/L
D. 0.45 mol/L
Answer:
Molarity = 0.27 M
Explanation:
Given data:
Volume of solution = 820 mL (820/1000 = 0.82L)
Mass of KI = 36.52 g
Molarity of solution = ?
Solution:
Number of moles of KI:
Number of moles = mass/molar mass
Number of moles = 36.52 g/ 166 g/mol
Number of moles = 0.22 mol
Molarity = number of moles / volume in L
Molarity = 0.22 mol / 0.82 L
Molarity = 0.27 M
NH4I(s) NH3(g) HI(g) Calculate the equilibrium concentration of HI when 0.343 moles of NH4I(s) are introduced into a 1.00 L vessel at 673 K. [HI]
This question is incomplete, the complete question is;
The equilibrium constant, Kc, for the following reaction is 7.00×10-5 at 673 K. NH4I(s) ---> NH3(g) + HI(g) Calculate the equilibrium concentration of HI when 0.343 moles of NH4I(s) are introduced into a 1.00 L vessel at 673 K
Answer:
the equilibrium concentration of HI is 1.302 × 10⁻⁵ M
Explanation:
Given that;
kc = 7.00 × 10⁻⁵ at 673 K
equilibrium concentration of HI = ?
when 0.343 moles of NH4I(s) are introduced into a 1.00 L vessel at 673 K
Molarity of NH4I = 0.343 / 1.00 = 0.343 M
NH4I(s) -----------------> NH3(g) + HI(g)
0.343 0 0 ------> Initial
(0.343 - x) x x -------> equilibrium
we know that; solid does not take part in equilibrium constant expression
so
KC = [NH3] [HI] / NH4I
we substitute
7.00 × 10⁻⁵ = x² / (0.343 - x)
0.00007 (0.343 - x) = x²
0.00002401 - 0.00007x = x²
x² + 0.00007x - 0.00002401 = 0
using; x = -b±√(b² - 4ac) / 2a
we substitute
x = -0.00007 ± √((0.00007)² - 4×1×-0.00002401) / 2×1
x = [-0.00007 ± √( 4.9×10⁻⁹ + 9.604×10⁻⁵)] / 2
x = [-0.00007 ± 0.00009604] / 2
Acceptable value of x = [-0.00007 + 0.00009604] / 2
x = 0.00002604 /2
x = 0.00001302 ≈ 1.302 × 10⁻⁵ M
therefore the equilibrium concentration of HI is 1.302 × 10⁻⁵ M
Which of the following is a chemical property?
O volume
O flammability
O color
O weight
Answer:
your answer is flammability
write an ionic equation for the reaction of nitric v acid and solid carbonate
Answer:
[tex]CO3^{2-}[/tex] + [tex]2H3O^{+}[/tex] => [tex]2H2O[/tex] + [tex]CO2[/tex]
Explanation:
Nitric acid reacts with sodium carbonate to form sodium nitrate, carbon dioxide and water.
Sodium carbonate + nitric acid => sodium nitrate + water + carbon dioxide
2HNO3 + Na2O3 => 2NaNO3 + CO2 + H2O
So the net ionic equation is as follows:
[tex]CO3^{2-}[/tex] + [tex]2H3O^{+}[/tex] => [tex]2H2O[/tex] + [tex]CO2[/tex]
The sodium ion and the nitrate ions are not involved in the net equation because they are not changed in the reaction.
What is the maximum number of electrons that an L shell may contain?
Answer:
Eight
Explanation:
The L shell only holds eight electrons.
8
The L shell can only holds eight electrons
What type of resource are fossil fuels such as coal, oil, and natural gas?
They are non-renewable resources that formed when prehistoric plants and animals died and were gradually buried by layers of rock.
24. H.SO, has
a) Ionic bond
b) both lonic and covalent bonds
c) ionic covalent and coordinate bonds
d) covalent bond
Answer:
b
Explanation:
Both ionic and covalent bonds when it has dissolved into water it will become ionic compound but when it was in gas situation it was covalent compound.
A student walks 15 km in 3 hours. What is the student’s average speed?
A :45 km/h
B :5 km/h
12 : km/h
18 : km/h
Answer:
5 km/h
Explanation:
divide the hours to the distance
Pleas help!! ASAP
Explain the physical and chemical properties of water, including its different phase changes. Why is water so crítical for human life? Written as an paragraph/essay
Explanation:
physical properties of water
Water is a colourless and tasteless liquid. The molecules of water have extensive hydrogen bonds resulting in unusual properties in the condensed form. This also leads to high melting and boiling points. As compared to other liquids, water has a higher specific heat, thermal conductivity, surface tension, dipole moment, etc. These properties form the reason for its significance in the biosphere. Water is an excellent solvent and therefore it helps in the transportation of ions and molecules required for metabolism. It has a high latent heat of vaporization which helps in the regulation of body temperature.
______________________________________
Chemical properties of water
Water reacts with a lot of substances to form different compounds. Some significant reactions are as follows:
Amphoteric nature:
Water can act as both acid and base, which means that it is amphoteric in nature.
Example:
Acidic Behaviour: H2O(l)+NH3(aq) ⇌ H3O+(aq)+NH+4(aq)
Basic Behavior: H2O(l)+H2S(aq) ⇌ H3O+(aq)+HS−(aq)
Redox reactions:
Electropositive elements reduce water to hydrogen molecule. Thus, water is a great source of hydrogen. Let us see an example in this case:
2H2O(l)+2Na(s)→2NaOH(aq)+H2(g)
During the process of photosynthesis, water is oxidized to O2. As water can be oxidized and reduced, it is very useful in redox reactions.
Hydrolysis reaction
Water has a very strong hydrating tendency due to its dielectric constant. It dissolves many ionic compounds. Some covalent and ionic compounds can be hydrolyzed in water
__________________________________
Water is so critical for human life Because...
Water’s extensive capability to dissolve a variety of molecules has earned it the designation of “universal solvent,” and it is this ability that makes water such an invaluable life-sustaining force. On a biological level, water’s role as a solvent helps cells transport and use substances like oxygen or nutrients. Water-based solutions like blood help carry molecules to the necessary locations. Thus, water’s role as a solvent facilitates the transport of molecules like oxygen for respiration and has a major impact on the ability of drugs to reach their targets in the body.
The energy of the universe is constant. That what mentioned by the first law of thermodynamics,
Does this mean that AE is always equal to zero?
Select one:
a. Yes, AE = 0 at all times, which is why q = -W
b. No, AE does not always equal zero because it refers to the system's internal energy, which is
affected by heat and work.
c. No, AE never equals zero because work is always being done on the system or by the
system.
d. No, AE does not always equal zero, but this is only due to factors like friction and heat.
e. No, AE never equals zero because energy is always flowing between the system and
surroundings.
Answer:
No, ΔE does not always equal zero because it refers to the systems internal energy, which is affected by heat and work
Explanation:
According to the first law of thermodynamics, energy is neither created nor destroyed. This implies that the total energy of a system is always a constant.
So, according to the first law of thermodynamics we have that ΔE = q + w. This means that the value of ΔE depends on q (heat) and w(work). Hence ΔE is not always zero since it depends on the respective values of q and w.
Perform the following calculations and report each answer with the correct number of significant figures.
a. 628 × 342 b. 5.45 – 2.3 c. 28.0/13.483
d. 14.98 + 27,340 + 84.7593
Answer:
Answers are given below
Explanation:
Significant figures:
When we add or subtract the values the number of significant figures after decimal in result must be equal to the given measurement having less number of decimal places.
b) 5.45 -2.3
3.2
d) 14.98 + 27,340 + 84.7593
27439.74
When we multiply or divide the values the number of significant figures must be equal to the less number of significant figures in given value.
a) 628 × 342
214776
we will round off this value into 3 significant figures.
215000
c) 28.0/13.483
2.08
Of the choices below, which is the most abundant gas in Earth's atmosphere?
Practice
A
argon
B
nitrogen
C
carbon dioxide
D
oxygen
Answer:
B. Nitrogen
Explanation:
Hope this helps :)
The answer is nitrogen gas.
Adenosine triphosphate is the energy source for work in the cell. It provides energy to the cell and ?
A. deactivates compounds for some reactions by transferring a phosphate group.
B. transfers its adenosine group to DNA.
C. activates compounds for some reactions by transferring a phosphate group.
D. activates enzymes by transferring phosphate groups to change the shape of the enzyme. lol
Answer:
C. activates compounds for some reactions by transferring a phosphate group.
Explanation:
Adenosine triphosphate, also known as ATP, is an energy carrier molecule used by the cells of living organisms to carry out their cellular function. ATP has the peculiar ability to store and release energy needed to do work. This energy is stored when a phosphate molecule is added to ADP to form ATP while it is released when the last phosphate group is removed to form ADP.
ATP supplies energy to compounds by transferring one of its phosphate molecules to it in a process called PHOSPHORYLATION. This transfer causes the compound to be activated for the cellular process it is about to undergo.
Write a balanced chemical equation that shows the formation of 2,3-dimethyl-1-butanol from the elements carbon (C), hydrogen (H2 ), and oxygen (O2 ). (Use the smallest integer coefficients possible and do not include states. Enter the elements in the order: C, H, then O in the product box.)
Answer:
12C + 14H₂ + O₂ = 2C₆H₁₃OH .
Explanation:
2,3-dimethyl-1-butanol
= CH₃-CH(CH₃)-CH(CH₃)-CH₂OH.
Molecular formula = C₆H₁₃OH .
= C₆H₁₄O
12C + 14H₂ + O₂ = 2C₆H₁₃OH .
burning magnesium is introduced into steam
Answer:
It produces magnesium oxide and hydrogen gas.
Explanation:
When magnesium burns with steam it produces magnesium oxide which is white in color and hydrogen gas. When magnesium burns, it mixes with the oxygen present in the air produces magnesium oxide in powder form. Magnesium react with oxygen by giving two electrons present in its valance shells while the oxygen needs two electron for completing their valance shell and becomes stable.
Bleach is more basic than egg whites.
Bleach is more basic than egg whites.
Egg whites are more basic than bleach.
Egg whites are more basic than bleach.
Bleach is more acidic than egg whites.
Bleach is more acidic than egg whites.
Egg whites are more acidic than bleach.
Please answer!!! Will give brainliest to best answer!!
1. What is the difference between magma and lava?
2. Under what circumstances do large crystals form from a cooling magma?
3. Under what circumstances do small crystals form from a cooling magma?
4. What happens to the mineral particles in salt water when the water evaporates?
5. Explain how halite forms.
6. Explain how mineral veins form.
Answer:
I can answer 1, lqva is magma outside of the volcano
If you are heating something, you can step away for a moment, as long as you come back very quickly.
a. True
b. False
Answer: b. False
Explanation:
The more energetic molecules move to a gas, spread out, and form bubbles when heating happens. When exposed to heat, many of the chemicals used in the laboratory are volatile and harmful (fire).
So leaving a material that you heat for even a second can be very hazardous and negligent.
Explain what is meant by a half-life of 150 years. Then, write a function that models the amount, A, of a 100-mg sample remaining after T years for a substance with a half-life of 150 years. Use graphing software to graph the equation. Answer in complete sentences.
Answer:
Half-life of 150 years are those year that a radioactive element take to disintegrate to a half of it's original value.
I don't have graphical software
PLS HELP ASAP 50 POINTS
The two main factors keep a planet in motion are what and what?
Answer:
Gravity, Inertia, and Velocity ( I decided to use three)
Explanation:
Gravity is the primary force that controls orbit and gravity works with inertia along with velocity.
Gravity, Inertia, and Velocity ( I decided to use three)
Explanation:
Gravity is the primary force that controls orbit and gravity works with inertia along with velocity.
The energy transformations shown below document the
changes that are a part of what energy resource?
Kinetic --> Mechanical --> Electrical
Solar Enega
Nuclear Energy
o Wind Energy
Fossil Fuels
A vessel of volume 100ml contains 10% of oxygen and 90% of an unknown gas. The gases diffuses in 86 second through a small hole of vessel.
If pure oxygen under similar
conditions and diffuses in 75 second, find the molecular weight of unknown gas?
The molecular weight of unknown gas : 23.46 g/mol
Further explanationGiven
A vessel contains 10% of oxygen and 90% of an unknown gas.
diffuses rate of mixed gas = 86 s
diffuses rate of O₂ = 75 s
Required
the molecular weight of unknown gas (M)
Solution
The molecular weight of mixed gas :(M O₂=32 g/mol)
[tex]\tt 0.1\times 32+0.9\times M=3.2+0.9M[/tex]
Graham's Law :
[tex]\tt \dfrac{r_{O_2}}{r_{mixed~gas}}=\sqrt{\dfrac{M_{mixed}}{M_{O_2}} }\\\\\dfrac{75}{86}=\sqrt{\dfrac{3.2+0.9M}{32} }\\\\0.76=\dfrac{3.2+0.9M}{32}\\\\24.32=3.2+0.9M\\\\21.12=0.9M\rightarrow M=23.46~g/mol[/tex]
A beaker of water is initially saturated with dissolved air. Explain what heppens whe he gas at 1 atm is bubbled through the solution for a long time.
Answer:
The bubble goes into the atmosphere.
Explanation:
All the dissolved air evaporated from the water when there is 1 atmospheric pressure for a long time because the air is dissolved with high pressure so when the pressure is removed from the gas present in water. The bubble go away from the water solution due to more kinetic energy present in it as compared to lower atmospheric pressure.
____describes a
solution in which the amount of
solute dissolved in a given amount
of solvent is less than
the solubility limit.
A. Soluble
B. Supersaturated
C. Saturated
D. Unsaturated
Oxygen (O2) and nitrogen (N2) are:_______ a. the major gaseous byproducts of combustion. b. the major gases that make up both troposphere and stratosphere c. the major gases that make up only the troposphere d. the major gases that make up only the stratosphere
Answer:
c. the major gases that make up only the troposphere
Explanation:
Oxygen (O2) and nitrogen (N2) are the major gases that make up only the troposphere because both oxygen and nitrogen are heavy gases which is present at lower height so it comes under the troposphere layer while on the other hand, ozone gas that act as a filter for harmful radiation of the sun is present in the stratosphere which is present next to troposphere layer of atmosphere.
Suppose a student made a different sodium hydroxide solution using 0.401g of solid sodium hydroxide and 200mL of water. The student then standardized this solution using benzoic acid in a similar manner to that depicted in the simulation. From the following additional data recorded by the student: a) Mass of benzoic acid: 0.158g b) Volumer of the benzoic acid solution: 100.0mL c) Volume of sodium hydroxide need to neutralize the solution: 27.84mL Determine the molarity of the sodium hydroxide solution.
Answer:
0.05 M
Explanation:
Mass of benzoic acid= 0.158g
Volume of benzoic acid= 100 mL
Volume of sodium hydroxide = 27.84mL
Molar mass of benzoic acid= 122g/mol
Number of moles of benzoic acid= 0.158g/122g/mol= 1.3 × 10^-3 moles
C= no of moles/volume
C= 1.3 × 10^-3 moles × 1000/100
C= 0.013M
So;
Volume of acid VA = 100mL
Concentration of acid CA= 0.013M
Volume of Base VB = 27.84mL
Concentration of Base CB= ???
Number of moles of acid NA =1
Number of moles of Base NB= 1
From;
CAVA/CBVB= NA/NB
CAVANB= CBVBNA
CB= CAVANB/VBNA
CB= 0.013 × 100 × 1/27.84 × 1
CB= 0.05 M
Which one of the following is most likely to be an ionic compound? SO2
Answer:
Ionic compounds generally form between elements that are metals and elements that are nonmetals. For example, the metal calcium (Ca) and the nonmetal chlorine (Cl) form the ionic compound calcium chloride (CaCl2). In this compound, there are two negative chloride ions for each positive calcium ion