Answer:
Halogens
Explanation:
Matter is defined as a substance which has mass and occupies volume. The three states of matter are solid, liquid and gas.
Elements which are present in group 17 are known as halogens.
Elements present in this group are fluorine, chlorine, bromine and iodine.
At room temperature, both fluorine and chlorine exists as a gas.
Bromine exists as a liquid and iodine exists as a solid.
Therefore, we can conclude that halogen groups are likely to have elements in three states of matter.
why is an element considered a pure substance
Answer:
Because they cannot be separated into more then one type of substance.
Explanation:
Answer:
Elements are made of only one kind of atom. The particles can be a single atom or a molecule made of only one kind of atom. There is no physical change that can separate elements into more than one kind of substance. This makes an element a pure substance.An element is made up of only one type of atom. An element cannot be broken down into a simpler form.
Describe the reaction of an acid with an alkali.?
Your question has been heard loud and clear.
The reaction of an acid with an alkali is neutralization reaction. It is a neutralization reaction because , they both neutralize each other (means it makes them chemically inactive after reacting) and produce a salt , and maybe water too.
An example: hydrochloric acid + sodium hydroxide → sodium chloride + water
Thank you
it will neutralise because if you add both of them together with a matching Ph such as 5 and 9 equally then it will neutralise and have a Ph of 7
could you please make me brainliest
Which of the following is not an antioxidant _________
1) Sodium benzoate 2) Sulphur dioxide 3) Sulphite salts 4) Citric acid
Answer: 1. Sodium Benzoate
Explanation: An anti-oxidant is a substance that can help prevent or stop the damage done by free radicals. Examples include; Sulphur Dioxide, Sulphite Salts, Citric Acid, e.t.c
Sodium benzoate is a pure preservative.
You work in the special effects department of a movie studio. You are
currently working on a superhero movie where the hero is very strong
and can punch through metal. For the next scene you need to replace a
6 inch by 6 inch square of a metal wall with a different material that will
crumble when the actor hits it. What could you use?
A. You could use Carbon(C)
B. You could use Potassium (k)
C. You could use Titanium (T)
D. You could use Manganese (Mn)
Answer:
The correct option is;
D. Manganese (Mn)
Explanation:
Manganese is very brittle, hard, iron like silvery-gray metal, that is difficult to melt. In air, Manganese slowly disintegrate in a similar manner to iron rusting in water
Manganese and iron have similar chemical and physical properties however manganese is more harder and more brittle than iron
A brittle material is one that easily breaks without deforming elastically
Therefore, manganese, due to its very iron like appearance and brittle nature will be suitable to replace the metal wall and crumble easily when the actor hits it.
Chemical change example
Answer: burning paper
Explanation:
The paper burns in air to form smoke and ash. which makes it a chemical change.
how many primary carbon are in 2,3 dimethylpentane
Answer:
There are 7 carbons in 2,3 dimethylpentane
Explanation:
Because 2,3-dimethlypentane is an organic compound of carbon and hydrogen with formula C7H16
What is the complete ionic equation for this reaction?
2KOH(aq) + H2SO4(aq) → 2H20(1) + K2SO4(aq)
O A. 2K+ + OH + H2SO4 → OH + 2H+ + K2SO4
B. OH + 2H+ + 2H20()
C. 2KOH + H2SO4 → 2H20 + K2SO4
D. 2K+ + OH + 2H+ + SO42- → 2H20() + 2K+ + SO42-
SUBMIT
Answer:
The answer is "Option D".
Explanation:
The entire ionic equation for all the substances, which are ionic compounds but are available in an aquatic is represented in the form with ions in the full ionic equation.
In the Net ionic equation, it doesn't have the particulate matter throughout the net ionic equations throughout the equations.
In the Spectator ions, it doesn't participate in interactions mostly on reaction and the material hand. From both sides, the very same ions are present.
The evenly balanced chemical formula is,
[tex]2KOH (aq)+ H_2SO_4(aq) \longrightarrow 2H_2O(l) + K_2SO_4[/tex]
It is the separate organic compound that full ion formula will match the choice D.
Which of the following processes is exothermic? Group of answer choices Allowing meat to thaw after taking it out of the freezer Popsicle melting on a warm summer day Boiling water in a beaker to convert it to steam Rolling a ball up a hill Reacting hydrogen and oxygen gases to make water
Answer:
Reacting hydrogen and oxygen gases to make water
Explanation:
Exothermic means that energy is released into the environment, so let's go through the process of elimination.
Allowing meat to thaw after taking it out of the freezer - NO it is endothermic, and takes energy/heat from the environment to thaw.
Popsicle melting on a warm summer day - NO also endothermic, the opposite of exothermic.
Boiling water in a beaker to convert it to steam - NO because we need to add heat, so it doesn't release any energy.
Rolling a ball up a hill - NO, for a ball to roll up a hill, it needs energy from something else, so it's not exothermic.
Reacting hydrogen and oxygen gases to make water - YES this reaction makes new bonds, which releases energy, so this is exothermic.
Among the following choices reacting hydrogen and oxygen gases to make water is an exothermic reaction as it releases energy as new bonds are formed.
What is an exothermic reaction?An exothermic reaction is defined as a chemical reaction which involves release of energy in the form of light,heat .In these reactions, energy is transferred from system to surroundings rather than taking energy from surroundings into system as in endothermic reactions.
In an exothermic reaction,change in enthalpy is negative.Therefore, it can be inferred that net amount of energy which is required to start the exothermic reaction is less than the net amount which is released by the reaction.
Examples of exothermic reactions are combustion reactions, detonation of nitroglycerin , neutralization reactions and nuclear fission.
Learn more about exothermic reactions,here:
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Increasing temperature can
When a substance's particles are packed together tightly and have a definite shape and
volume...it is said to be in what state?
solid
gas
plasma
liquid
Answer:
solid
Explanation:
Answer in the correct significant figures: 35.6 + 56.27 *
Answer:
101.87
Explanation:
that's the answer
What is the product of the reaction of pentanoic acid with ethanol in the presence of a strong acid?
Answer:
ethylpentanoate
Explanation:
Alkanoic acids react with alkanols in the presence of mineral acids to yield an ester and water. This is the organic analogue of the inorganic neutralization reaction. The reaction his commonly called esterification. It is an acid catalysed reaction.
The reaction of pentanoic acid and ethanol in the presence of a string acid is shown below;
CH3CH2CH2CH2COOH(aq) + CH3CH2OH(aq) ----> CH3CH2CH2CH2COOCH2CH3(aq) + H2O(l)
The name of the compound formed is ethylpentanoate.
Os subníveis mais energéticos de um dado átomo são: ...4s2 3d10 4p5 a) indique o seu número atomico b) quantos electrões de valência apresenta esse átomo c) a que família pertence?
Answer:
A. 35
B. 7
C. halogênios
Explanation:
Aqui, para responder a essa pergunta, precisaremos conhecer o elemento particular em questão.
..... 4s ^ 2 3d ^ 10 4p ^ 5 significa que está a cinco elétrons da configuração eletrônica do último elemento na primeira camada dos metais pesados.
O último elemento da 1ª série do elemento de transição é o zinco, portanto, como está a apenas 5 elementos de distância, o átomo de que estamos falando é o átomo de Bromo de Bromo.
A. O zinco tem um número atômico 30 e como o bromo está a 5 elementos de distância, seu número atômico é 35
B. Uma vez que pertence ao grupo halogênio, tem 7 elétrons de valência como o resto da família
C. Pertence à família dos halogênios
3. How many meters above sea level is the base of your landform?
How many meters above sea level is the top of your platform?
Answer:
Base is 715 and top is 850.
Explanation:
715 meters above sea level is the base of my landform and 850 meters above sea level is the top of my platform. Base of landform from a sea level is a starting point of a city or region having same topography. This region has a specific height where it spreads we called it top of the platform. The starting point of my location is 715 meters above sea level spreads up to 850 meters of elevation.
The number of atoms in 2.0 moles of NaOH is _____ of 1.0 mole of H2O.
twice that
less than
more than
the same as
Answer:
The answer is the same as .
Explanation:
There are 3 atoms in NaOH, 1 sodium, 1 oxygen and 1 hydrogen.
There are 3 atoms in H2O, 2 hydrogen and 1 oxygen.
Examine the given reaction. NH4NO3(s) → NH4+(aq) + NO3–(aq) ΔH° = 25.45 kJ/mol ΔS° = 108.7 J/mol·K Which of the given is correct about the ΔG° at 25 °C?
A)+4,360 J
B)−6,942 J
C)−4,360 J
D)+6,942 J
Answer:
B)−6,942 J /mol
Explanation:
At constant temperature and pressure, you cand define the change in Gibbs free energy, ΔG, as:
ΔG = ΔH - TΔS
Where ΔH is enthalpy, T absolute temperature and ΔS change in entropy.
Replacing (25°C = 273 + 25 = 298K; 25.45kJ/mol = 25450J/mol):
ΔG = ΔH - TΔS
ΔG = 25450J/mol - 298K×108.7J/molK
ΔG = -6942.6J/mol
Right solution is:
B)−6,942 J /molwrite the formula of three compounds which you know and name the elements in them
Answer:
[tex]\boxed{\sf{view \ explanation}}[/tex]
Explanation:
Compound definition:
A compound is a chemical substance formed by two or more chemically bonded elements.
Three compounds:
Water is a compound with the formula [tex]\sf H_2O[/tex].
Two hydrogen atoms and one oxygen atom is present in one molecule of water.
Sodium chloride or table salt is a compound with the formula [tex]\sf NaCl[/tex].
One sodium atom and one chlorine atom is present in one molecule of sodium chloride.
Ammonia is a compound with the formula [tex]\sf NH_3[/tex].
In one molecule of ammonia, one nitrogen atom and three hydrogen atoms are present.
Answer:
See below
Explanation:
Three compounds are:
1) [tex]\mathrm {H_{2}SO{4}}[/tex] [Sulfuric acid]
The elements in this compound are hydrogen (H) , Sulfur (S) and Oxygen (O).
2) [tex]\mathrm {NaOH}[/tex] [Sodium hydroxide]
The elements in this compound are Sodium (Na) , Oxygen (O) and Hydrogen (H).
3) [tex]\mathrm {HCl}[/tex] [Hydrochloric acid]
The elements are Hydrogen (H) and Chlorine (Cl).
If the molarity of sugar is 1.1, what will the freezing point be?
Answer:
The freezing point will be -2.046°C.
Explanation:
The freezing point depression equation is [tex]\Delta T_f = k_f \cdot m \cdot i[/tex]
Where;
[tex]\Delta T_f[/tex] = The temperature depression of the freezing point
[tex]k_f[/tex]= The constant of freezing point depression which is solvent dependent = 1.86°C/m
i = The number of particles the substance decomposes into in solution = 1 for sugar (a covalent compound)
m = The molality of the solution = 1.1
Therefore, we have;
[tex]\Delta T_f = 1.86 \times 1.1 \times 1 = 2.046 ^{\circ}C[/tex]
Therefore the freezing point will be 0 - 2.046°C = -2.046°C.
It requires work to _____. A. stretch a spring only B. compress a spring only C. stretch or compress a spring
Answer:
C.
Explanation:
It requires work to stretch or compress a spring.
Answer:the answer is c
Explanation: i say that because with work you can do both of those things
Which of these is true about electrons? posses a positive electrical charge of one (+1) have a negative electrical charge of one (-1) indicates the number of protons in each atom equals the sum of protons plus neutrons in each atom
Answer:
have a negative electrical charge of one (-1)
Explanatio
Electrons have an electrical charge of negative one. When you think electron, always think -1
A chemical equation is balanced when Group of answer choices the number of atoms of each element is the same in reactants and products. the charge on each atom is the same in reactants and products. the sum of the coefficients of the reactants is equal to the sum of the coefficients of the products. the total number of ions is the same in reactants and products. the total number of molecules is the same in reactants and products.
Answer:
a
Explanation:
A chemical equation is said to balanced only when the number of atoms of each element is the same in both reactants and products side. Rest all options are absurd. Hence, option a is correct.
Balancing of the reaction has no relation with coefficient, molecules or charge of the elements
For the set of ionic compounds, CaSO4, CaCO3, Ca(OH)2, choose the correct characterization of their solubilities in water from the response list. Group of answer choices None of the three salts are soluble. All three salts are soluble. Two of the three salts are soluble. One of the three salts is soluble.
Answer:
None of the three salts are soluble.
Explanation:
According to the solubility rule, the carbonates and sulphates of group two elements are insoluble in water.
All three substances mentioned possess very low solubility in water and can be said to be slightly soluble in water. If we compare them with other ionic substances that dissolve readily in water, we can rightly say that they are insoluble in water.
Hence all three substances are insoluble in water.
Question 9 of 10
How could an electron configuration be used to predict relative atomic size?
A. The more valence electrons listed, the larger the atomic radius.
B. The larger the highest energy level number, the larger the atomic
radius.
C. The more sublevels occupied, the larger the atomic radius.
D. The greater number of total electrons, the larger the atomic radius.
SUBMIT
Answer: B
Explanation: Apex
An electron configuration be used to predict relative atomic size because the larger the highest energy level number, the larger the atomic
radius.
The electron configuration of an element shows the arrangement of electrons in atoms of that element.
As more sublevels are added, repulsion between electrons occupying shells increases causing a greater shielding and consequent increase in the size of the atom.
Hence, the larger the highest energy level number, the larger the atomic
radius.
Learn more: https://brainly.com/question/238050
What is the PRECAUTION for an Irritant?
pls balance the following chemical equation asap; Ca(OH)2 +CO2 = CaCO3+ H2O pls make it step by step
Answer:
Explanation:
Start by writing water as HOH
Ca(OH)2 +CO2 = CaCO3+ HOH
Next pay attention to the CO2 going to CO3
We need an oxygen.
Fortunately that is provided by the (OH)2
Now we have
Ca(OH)2 + CO2 ==> CaCO3 + HOH
and believe it or not, that is balanced as it is
The left side has 1 Ca. So does the right side
The Left side has 1 C. So does the right side.
The left side has 2 H. So does the right side
The left side has 2 oxygens (in Ca(OH2)) + 2 oxygens in CO2
So the equation is balanced.
Which bond type is found in ammonium chloride. Select one: a. metallic b. covalent c. ionic
Answer:
ionic
Explanation:
In NH4Cl molecule, ionic bond is formed between NH4+ and Cl– ions, 3 covalent bonds are formed between N and three H atoms and one coordinate bond is formed between N and 1 H atom.
HOPE IT HELPS :)
PLEASE MARK IT THE BRAINLIEST!
Answer:
[tex]\boxed{\sf c. \ ionic}[/tex]
Explanation:
NH₄Cl is formed by an ionic bond between NH₄⁺ and Cl⁻ ions.
NH₄Cl (solid) ⇒ NH4⁺ (aqueous) + Cl⁻ (aqueous)
what is mean by stakeholder
Answer:
a stakeholder is a party that has an interest in a company and can either effect or be affected by the business. the primary stakeholder in a typical corporation are its investors , employees, customers and supplies.please help :) How can scientists ensure that their data are reliable? A) by making a single observation B) by recording values without units C) by keeping the results private D) by repeating trials during an experiment
Answer:
D. by repeating trials during an experiment
Explanation:
chile its actually d
Explanation:
Undulation in sandy material is called
cross-beds
ripple marks
mud cracks
O fossils
Answer:
ripple marks
Explanation:
Undulation is defined as the to and fro wavelike motion in a fluid or elastic medium.
Undulation in sandy material is called ripple marks because ripple marks are the sediments of rocks that show wavy structure at its surface due to agitation by water and wind.
Hence, the correct answer is "ripple marks".
Lab Safety Rule #3 says to always add acids or bases to the solvent and NEVER the other way around true or false?
Answer:
true
Explanation:
The standard laboratory rule is to always add acids or bases to solvent and not the other way round.
The dissolution of concentrated acids/bases in solvents (water) generates heat energy. Thus, if the solvent is added to them, a layer of hot weak acid or base will be formed and this will boil and spray around, causing an explosion.
On the other hand, if acid/base is added to solvents, they flow into the solvents and get diluted immediately without any boiling taking place. Hence, it is safe to add acid/base to solvents and not the other way round.
