Answer:
materials which do not show the quality of lustre i.e. shiney surface
for eg- non metals except Iodine
Explanation:
hope it helps u plz mark as the brainliest
Answer:
These are materials that don't have lustre
Explanation:
They are not shiny.
They include non-metals but not iodine.
Hope it helps.
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:
what is organic chemistry
Answer:
Organic chemistry
Explanation:
Organic chemistry is part of the chemistry that studies carbon compounds, which also use organic compounds, which have characteristics.
In common speech, some people may use the terms hypothesis and theory interchangeably. In science, however, the terms have different meanings. What do you think is an important difference between a hypothesis and a theory?
Answer: In science, a hypothesis is a possible explanation for an observation, while a theory is an explanation that is supported by a large body of evidence.
Explanation: exact answer
What element is depicted by the following electron configuration:
(The electron configuration is in the image)
A. None of these
B. Oxygen
C. Chlorine
D. Sulfur
Explanation:
Your required answer is sulpher.
Hope it helps...
Answer the question in attachment and can I ask from which country you are.
I am new on this app.
✌️✌️☺️☺️
Answer:
1: exothermic
2:hydrated iron (III) oxide
3:reactants
4:precipitate
5: hydrogen gas
Answer:1.exothermic
2.hydrated iron (III) oxide
3.reactants
4.precipitate
5. hydrogen gas
3.87 moles of iron bromide yielded10.4 moles of sodium bromide
Answer: 89.57 %
Hope it helps
How many significant figures are in 0.08260 L? 4 5 6
Answer:
5
Explanation:
Count the digits after the first non zero number, any number after that (even zero) counts.
Hope that helped!!! k
Answer:
[tex]\boxed{4}[/tex]
Explanation:
[tex]\sf Leading \ zeros \ are \ not \ significant.[/tex]
[tex]\sf Trailing \ zeros \ are \ significant.[/tex]
[tex]\sf Non\ zeros \ are \ significant.[/tex]
[tex]0.08260 \sf \ has \ 4 \ significant \ figures.[/tex]
6th edition before we begin, let's first establish an understanding of basic terminology. it may be harder than you think to clearly define what is a chemical versus a chemical reaction. to help us better differentiate between closely related terms, review the words listed here. sort each of the words into the three categories: contains chemicals, chemical reaction, or neither.
Answer:
Chemicals are substances in any form of matter with a chemical composition and property. Chemical reaction involves the combination of two or more different atoms chemically combined together, which are not easily separated.
Explanation:
CHEMICALS
Vitamin [tex]B_{1}[/tex]proteingraniteorangesCHEMICAL REACTIONS
neutralisationcombustionbleachingphotosynthesisNEITHER
sunlightheatrainbowIt 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
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
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
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:
https://brainly.com/question/10373907
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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.
If a sample of aluminum with a density of 2.70 g/cm^3 displaces 36.0 mL of water when placed in a beaker, what is its mass?
13.3 g
97.2 g
0.075 g
Answer:
The answer is 97.2g .
Explanation:
Given that 1 mL is equals to 1 cm². Then we have to apply Density formula :
[tex]density = \frac{mass}{volume} [/tex]
[tex]let \: density = 2.7 \: , \: volume = 36[/tex]
[tex]2.7 = \frac{mass}{36} [/tex]
[tex]mass = 2.7 \times 36[/tex]
[tex]mass = 97.2 \: grams[/tex]
Answer in the correct significant figures: 31.2 x 4.13*
Answer:
1.29* 10^2
Explanation:
multiply them and then round
Answer in the correct significant figures: 35.6 + 56.27 *
Answer:
101.87
Explanation:
that's the answer
Why does science need to.change its view on ideas overtime?
Explanation:
A scientific idea is an explanation for how something works, or the truth about some aspect of the world, that was figured out using the scientific process. ... Scientific ideas change over time as the evidence improves. The more experiments they do , and the more data they collect, the better the scientific ideas become.
PLEASE PLEASE HELP!!!! What is the mass of a sample material that has a volume of 72.2cm³ and a density of 7.7g/cm³?
Answer:
The answer is
555.94g
Explanation:
To find the mass of a substance given it's density and volume we use the formula
[tex]Density \: = \frac{mass}{volume} [/tex]Making mass the subject we have
mass = Density × volume
From the question
Density = 7.7 g/cm³
Volume = 72.2 cm³
Substitute the values into the above formula
That's
mass = 7.7 g/cm³ × 72.2 cm³
We have the final answer as
mass = 555.94gHope this helps you
Which of the following polyatomic ions will form an ionic compound with two sodium ions? CO32− HCO31− NO21− NO31−
Answer:
CO32−
Explanation:
We have to consider the valencies of the polyatomic ions involved. Recall that it is only a polyatomic ion with a valency of -2 that can form a compound which requires two sodium ions.
When we look closely at the options, we will realize that among all the options, only CO32− has a valency of -2, hence it must be the required answer. In order to be double sure, we put down the ionic reaction equation as follows;
2Na^+(aq) + CO3^2-(aq) ---------> Na2CO3(aq)
Answer:
A). CO32−
Explanation:
You are given two aqueous solutions with different ionic solutes (Solution A and Solution B). What if you are told that Solution A has a greater concentration than Solution B by mass percent, but Solution B has a greater concentration than Solution A in terms of molality? Is this possible? If not, explain why not. If it is possible, provide example solutes for A and B and justify your answer with calculations.
Answer:
Yes, it is possible. Let us consider an example of two solutions, that is, solution A having 20 percent mass RbCl (rubidium chloride) and solution B is having 15 percent by mass NaCl or sodium chloride.
It is found that solution A is having more concentration in comparison to solution B in terms of mass percent. The formula for mass percent is,
% by mass = mass of solute/mass of solution * 100
Now the formula for molality is,
Molality = weight of solute/molecular weight of solute * 1000/ weight of solvent in grams
Now molality of solution A is,
m = 20/121 * 1000/80 (molecular weight of RbCl is 121 grams per mole)
m = 2.07
Now the molality of solution B is,
m = 15/58.5 * 1000/85
m = 3.02
Therefore, in terms of molality, the solution B is having greater concentration (3.02) in comparison to solution A (2.07).
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
What is the main factor responsible for the acidic and basic character of oxides?
Explain your answer.
Explanation:
We define non-metal oxide acidity in terms of the acidic solutions formed in reactions with water. For example, sulfur trioxide reacts with water to forms sulfuric acid. In sum, acidic oxides are oxides of non-metals, and basic oxides are oxides of metals. ... CrO is basic, Cr2O3 is amphoteric and CrO3 is acidic.Reply me in commentsexplain using diagrams how potassium forms the compound potassium flouride when it reacts with flourine
Answer:
The answer to your question is given below.
Explanation:
Potassium (K) has 19 electrons with electronic configuration of 2, 8, 8, 1.
Fluorine (F) has 9 electrons with electronic configuration of 2, 7.
Fluorine needs 1 electron to complete it's octet configuration.
Hence, potassium (K), will lose 1 electron to fluorine (F) to form potassium ion (K+) with electronic configuration of 2, 8, 8. The fluorine atom (F) will receive the 1 electron from potassium to form the fluoride ion (F-) with electronic configuration of 2, 8.
**** Please see attached photo for further details.
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.
what is the light transmission of gallium?
Explanation:
the intensity of a He-Ne laser (633 nm ,5 mW) transmitted by different Gase samples is observed to change in correlation with the Nd-yttrium-aluminium-garnet laser pulse (532 nm, 7.8ns ,3mJ) which excites them
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:
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.
An atom X has a proton number of 19 and relative atomic mass of 39.
(i) How many electrons, protons and neutrons are there in an atom of X?
(ii) How many electrons will there be in the outer energy level (shell) of an atom of X?
(iii) What is the electronic configuration of X?
Answer:
1) electron=19 Proton=19 Neutron=39-19=20
2) 1
3) in pic
Answer:
(i)electrons = 19; Protons = 19 Neutrons =39-19=20
(ii) 1
(iii) 2,8,8,1
Hope this helps.
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What are the requirements of any hypothesis in science?
Answer:
A scientific hypothesis must meet 2 requirements:
Explanation:
A scientific hypothesis must be testable, and;
A scientific hypothesis must be falsifiable.
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.