Answer:
True
Explanation:
Those bases which are soluble in water are called alkalis
Dry ice changes from a solid to a gas in a process known as A. Melting B. Freezing C.sublimation
Answer:
c
Explanation:
solid to gas directly
The total number of the elements above with 2 valence electron is ____.
Answer:
four elements
Explanation:
He = 1s²
Be = 1s² 2s²
C = 1s² 2s² 2p²
Mg = 1s² 2s² 2p⁶ 3s²
Si = 1s² 2s² 2p⁶ 3s² 3p²
Ca = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
Valence electrons are those electrons which are present in outer most electronic shell.
He, Be, Mg, Ca these four elements have 2 valence electrons.
While Si and C have four valance electrons.
The total number of the elements above with 2 valence electron is four.
The electronic configurations of the elements are given:
He = 1s²
Be = 1s² 2s²
C = 1s² 2s² 2p²
Mg = 1s² 2s² 2p⁶ 3s²
Si = 1s² 2s² 2p⁶ 3s² 3p²
Ca = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
Valence electrons are those electrons which are present in outer most electronic shell.
He, Be, Mg, Ca these four elements have 2 valence electrons.Learn more:
brainly.com/question/16089134
A 0.200 M NaOH solution was used to titrate a 18.25 mL HE
solution. The endpoint was reached after 31.20 mL of titrant
were added. Find the molar concentration of the original HF
solution.
Answer:
M₂ = 0.34 M
Explanation:
Given data:
Molarity of NaOH =M₁ = 0.200 M
Volume of HF =V₂= 18.25 mL
Volume of NaOH added = V₁ = 31.20 mL
Molarity of HF solution = M₂ = ?
Solution:
M₁V₁ = M₂V₂
by putting values,
0.200 M × 31.20 mL = M₂ × 18.25 mL
M₂ = 0.200 M × 31.20 mL / 18.25 mL
M₂ = 6.24 M.mL / 18.25 mL
M₂ = 0.34 M
When can I use ideal gas law?
1. List the types of fronts found on this map
Answer:
Cold Front. A side view of a cold front (A, top) and how it is represented on a weather map (B, bottom). ...
Warm Front. ...
Stationary Front. ...
Occluded Front.
What type of fish is this?
Answer:
Angel Fish!
Explanation:
Answer:
Angel fish, the other person answered first tho.
Explanation:
How does Cyanoacrylate compare to the elements that make it up?
Answer: The elements of the cyanoacrylate are different as compared to the main cyanoacrylate.
Explanation:
The cyanoacrylate is a adhesive water based substance. It is used for developing fingerprints by fuming method. It is the acrylic monomer which has property to develop into a plastic form after application another of its composition is the acrylic resin which imparts adhesiveness to the cyanoacrylate.
Elimination of HBr from 2-bromobutane affords a mixture of but-1-ene and but-2-ene. With sodium ethoxide as base, but-2-ene constitutes 81% of the alkene products, but with potassium tert-butoxide, but-2-ene constitutes only 67% of the alkene products. Offer an explanation for this difference.
Answer:
see explanation
Explanation:
The elimination reaction involving 2-bromobutane leads to the formation of two products with the predominant product depending on the nature of the base used.
With a bulky base such as potassium tert-butoxide, the secondary carbon atom is inaccessible due to steric hindrance. Therefore, but-1-ene predominates (higher percentage).
However, when a less bulky base such as sodium ethoxide is used, the secondary carbon atom is more easily accessible, leading to the predominant formation of the thermodynamically favourable but-2-ene.
Explain Joule's law in your own words. pls help
Answer:
Joules first law is a law that expresses the relatioship between heat that is generated and the current flowing heat thats through a conductor. The second law says that internal energy is independent of volume and pressure, depending only on temperature!
Explanation:
The transfer of thermal energy from a warmer object to a cooler object is called
Answer:
heat transfer
For the cold pack shown below, the temperature on the outside surface has dropped considerably from its initial temperature of 25 °C. Which of the following provides the best explanation for this temperature decrease?
Answer:
The correct answer is D
Explanation:
In an endothermic process, energy travels from the surroundings into the system. The decrease in the temperature on the outside of the bag indicates that energy has moved from the surroundings into the system.
The other answers are incorrect. A bag cannot release “cold” into the surroundings since cold refers to the absence of heat. The surroundings become colder when heat is removed. Option B is incorrect because the cooling is due to the cold pack absorbing heat energy from its surroundings. Option C is incorrect because a cold pack absorbs heat energy from the surroundings, not vice versa.
The surroundings are losing energy and the thermometer is measuring the temperature of the surroundings as the cold pack shows an endothermic process. Therefore, Option (D) is correct.
What is an endothermic reaction?Endothermic reactions are those in which the reactants absorb heat energy from their surroundings to form products. Endothermic reactions reduce the temperature of their surroundings and create a cooling effect. Physical processes can be endothermic in nature as well, for example, ice cubes absorb heat from their surroundings to form liquid water.
Endothermic reactions include the making of chemical bonds through the absorption of energy from the surroundings. On the other hand, exothermic reactions are in which the liberation of heat energy is generated from bond breakage.
The temperature of the cold pack is lower than the temperature of the surroundings. So the heat energy will be traveled from the surroundings to the cold pack.
Therefore, the temperature of the surroundings will fall as heat transfers to the cold pack.
Learn more about endothermic reactions, here:
https://brainly.com/question/23184814
#SPJ2
PLEASE ANSWER QUICK! 50 POINTS!!!!
How does the structure of amino acids allow them to form a polypeptide?
Options:
A. Each amino acid has an amino group and a carboxyl group.
B. Each amino acid has a hydrogen atom and a carboxyl group.
C. Each amino acid has a carboxyl group and an R group.
D. Each amino acid has an R group and a hydrogen atom.
Answer:
A. Each amino acid has an amino group and a carboxyl group.
Answer:a
Explanation:
how can you tell which compound in a solution is the solvent?
(own words please)
Answer:
The way you can know which compound in a solution is a solvent is by usually just determining which substance is a solute and which is a solvent. The solute is when it is dissolved and it takes on the characteristics of the solvent.
Explanation:
Hope this helps!
If a concentrated solution of acetic acid is 99.5 % HC 2 H 3 O 2 and has a density of 1.05 g/mL, what is the concentration of this acid in moles per litre?
The concentration of this acid in moles per litre : 17.41
Further explanationGiven
99.5% acetic acid
density=ρ=1.05 g/ml
Required
the concentration (mol/L)
Solution
99.5% dan density 1.05 g/ml (MW acetic acid = 60 g/mol)
[tex]\tt 99.5\%\times 1.05\dfrac{g}{ml}\times \dfrac{1000~ml}{L}=1044.75~g/L\\\\\dfrac{1044.75~g/L}{60~g/mol}=17.41~mol/L[/tex]
BRAINLIEST!! PLZ HELP
Answer:
1.0 is Answer
Explanation:
May be this is helpful!
does something that is hot have more thermal energy than something that’s cold?
Answer:
Yes it does because the atoms/molecules are moving faster than they are in a cold substance.
Explanation:
what is an example of a chemical change that occurs during weathering
Answer:
Hydrolysis is a chemical wheathering process that may affect silicates and carbonates minerals. an example of such a reaction in which water reacts with a silicates minerals is the following: Mg2SiO4 + 4H2O ⇄ 2 Mg(OH)2 + H4SiO. olivine (forsterite) + water ⇄ brucite + silicic acid.
Explanation:
Wass, volume and density are all properties of
matter
3
weight.
formula
Answer:
:)
Explanation:
They are all properties of Matter. weight and formula wouldn't make sense.
Neeeeeeeedddddd hellllllllllppppppp
Aluminum metal reacts with hydrochloric acid to produce solid aluminum chloride and hydrogen gas. how many moles of aluminum are needed to produce 1.2 moles of hydrogen gas?
Moles of Aluminum needed : 0.8
Further explanationGiven
1.2 moles H₂
Required
moles of aluminum
Solution
The reaction coefficient in a chemical equation shows the mole ratio of the components of the compounds involved in the reaction (reactants and products)
Reaction(balanced equation)
2Al + 6 HCl = 2AlCl₃ + 3H₂
From the equation, mol ratio of Al : H₂ = 2 : 3, so mol Al :
= 2/3 x mol H₂
= 2/3 x 1.2
= 0.8 moles
17. Calculate the percent composition of B2Br6
Answer:
%composition of B₂ = 4.3%
%composition of Br₆ = 95.7%
Explanation:
Given data:
Percent composition of B₂Br₆ = ?
Solution:
Total mass of B₂Br₆ = 10.8×2 + 79.9×6 = 501 g/mol
%composition of B₂ = ( 21.6 g/ 501 g ) × 100
%composition of B₂ = 0.043 × 100
%composition of B₂ = 4.3%
%composition of Br₆ = ( 479.4 g/ 501 g ) × 100
%composition of Br₆ = 0.957 × 100
%composition of Br₆ = 95.7%
Calculate the maximum mass of aluminium which can be extracted from 10 kg of
aluminium oxide
2AlO3+ 3C ----->4Al + 3CO2
Answer:
Hrishikesh. bshjsjbd. jwjjja
which term refers to the condition that exists when no over all change in concentration results from diffusion?
a. concentration
b. osmosis
c. equilibrium
d. randomness
Answer:
a.cocentration es la respuesta
An object at rest has equal forces acting on it. This can be described as a __________ force.
What is the molarity of a solution
made by dissolving 18.9 g of
ammonium nitrate (NH4NO3) in
enough water to make 855 mL of
solution?
Molar Mass N: 14.01 g/mol
Molar Mass H: 1.008 g/mol
Molar Mass O: 16.00 g/mol
Answer:
Molarity = 0.28 M
Explanation:
Given data:
Mass of NH₄NO₃ = 18.9 g
Volume of solution = 855 mL (855mL × 1 L/1000 mL = 0.855 L)
Molarity of solution = ?
Solution:
Number of moles of NH₄NO₃:
Number of moles = mass/molar mass
Number of moles = 18.9 g/ 80.043 g/mol
Number of moles = 0.24 mol
Molarity:
Molarity = number of moles of solute / volume in L
Molarity = 0.24 mol /0.855 L
Molarity = 0.28 M
Answer:
0.28
Explanation:
:D
A gas with a volume of 2 L at 25°C is placed into a container that is 4 L. What is the new temperature of the gas?
Given :
A gas with a volume of 2 L at 25°C is placed into a container that is 4 L.
To Find :
The new temperature of the gas.
Solution :
Since, their is no information regarding pressure. We will assume that pressure is constant.
Now, we know when at constant pressure, volume is directly proportional to volume.
[tex]\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}\\\\\dfrac{2}{4} = \dfrac{25 + 273 }{x}\\\\x = 2 \times ( 25 + 273 )\\\\x = 596\ K[/tex]
Therefore, the new temperature of the gas is 596 - 273 K = 323 K.
Under which conditions will sugar most likely dissolve fastest in a cup of water?
A. A sugar cube with stirring at 5°C
B. A sugar cube without stirring at 15°C
C. Sugar crystals with stirring at 15°C
D. Sugar crystals without stirring at 5°C
Answer:
The correct answer would be C
Explanation:
Plz correct me if wrong
The condition in which sugar is most likely to dissolve fastest in a cup of water is when sugar crystals with stirring at 15°C. Therefore, option C is correct.
What conditions are required for dissolution?Dissolution is the process by which a solute dissolves in a solvent to form a homogeneous mixture called a solution. The conditions required for dissolution are:
Agitation: The solute and solvent must be mixed together so that they come into contact with each other.Temperature: Increasing the temperature of the solvent increases the kinetic energy of its molecules, making it easier for the solute to dissolve.Pressure: Increasing the pressure of a gas above a liquid solvent can force more gas molecules into the solvent, increasing its solubility.Surface area: The rate of dissolution is directly proportional to the surface area of the solute particles exposed to the solvent. Polarity: A solute will dissolve in a solvent that has similar polarity.Thus, option C is correct.
Learn more about dissolution, here:
https://brainly.com/question/9949108
#SPJ5
How much of earth's freshwater is in the solid state or under ground?
That would be B: 33%, but please correct me if I'm wrong ^^
Answer:
that would be b:33 i believe pls dont blame met
3. A 240 mL sample of argon gas at 270 K is cooled until the volume is 180 mL. What is the new temperature?
Answer:
202.5 K
Explanation:
What element am I if I have 6 protons and
8 neutrons?
Answer:
The element you would have is Carbon-14.
Explanation:
Carbon-14 has 6 protons and 8 neutrons. To find the atomic mass, you add the protons to the neutrons, so the atomic mass of Carbon-14 is 14.
#teamtrees #WAP (Water And Plant)