Answer:
Because the scientific knowledge itself helps solve many basic human needs and it also improves how humans live and their standards. For example, without science medications wouldn´t exist and many technological devices we use now-a-days. We´re surrounded by science, we just don´t really notice it.
Suggest two reactants to prepare sodium nitrate by titration
Answer:
HNO3 and NaOH
Explanation:
A neutralization reaction is a reaction that occurs between an acid and a base to form salt and water only.
Neutralization reactions are commonly carried out by method of titration. That is, a measured volume of acid of unknown concentration is made to react with a known volume of standard base solution or vice versa.
Two reactants that could be titrated to obtain sodium nitrate are nitric acid and sodium hydroxide.
The reaction equation is as follows;
HNO3(aq) + NaOH(aq) ----> NaNO3(aq) + H2O
Cheese is an example of Solid in gas colloid Liquid in gas colloid Solid in liquid colloid Liquid in solid colloid
Two billiard balls having masses of 0.2 kg and 0.15kg approach each other. The first ball having a velocity of 2m/s hit the second ball which is at rest. What will be the velocity of the first ball if the second ball travels at 1.5 m/s after collision?
Answer: The velocity of the first ball is 0.875 m/s if the second ball travels at 1.5 m/s after collision.
Explanation:
Given: [tex]m_{1}[/tex] = 0.2 kg, [tex]m_{2}[/tex] = 0.15 kg
[tex]v_{1}[/tex] = 2 m/s, [tex]v_{2}[/tex] = 0 m/s, [tex]v'_{1}[/tex] = ?, [tex]v'_{2}[/tex] = 1.5 m/s
Formula used is as follows.
[tex]m_{1}v_{1} + m_{2}v_{2} = m_{1}v'_{1} + m_{2}v'_{2}[/tex]
where,
v = velocity before collision
v' = velocity after collision
Substitute the values into above formula as follows.
[tex]m_{1}v_{1} + m_{2}v_{2} = m_{1}v'_{1} + m_{2}v'_{2}\\0.2 kg \times 2 m/s + 0.15 kg \times 0 m/s = 0.2 kg \times v'_{1} + 0.15 kg \times 1.5 m/s\\0.4 kg m/s + 0 = 0.2v'_{1} + 0.225 kg m/s\\0.2v'_{1} kg = 0.175 kg m/s\\v'_{1} = \frac{0.175 kg m/s}{0.2 kg}\\= 0.875 m/s[/tex]
Thus, we can conclude that the velocity of the first ball is 0.875 m/s if the second ball travels at 1.5 m/s after collision.
rare earth elements plz
Answer:
Rare earth elements are lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, yttrium - that appear in low concentrations in the ground.
Explanation:
The rare earth elements (REE) are a set of seventeen metallic elements. These include the fifteen lanthanides on the periodic table plus scandium and yttrium. Rare earth elements are an essential part of many high-tech devices.
Which 3 organisms feed on dead matter and waste products?
Earthworm
Ladybug
Fungi
Mice
Bacteria
Answer:
mice
bacteria
fungi
Explanation:
that's the answer
What is lassaigne's test?
Answer:
The Lassaigne's test, also known as
the sodium fusion test, is used in
elemental analysis to determine the
presenceof foreign elements,
specifically halogens, nitrogen, and
sulfur, in an organic compound.
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'Synthetic detergents are better than soaps'. Justify this statement
Answer:
Synthetic detergents can be used for washing purposes even when the water is hard, whereas soaps are not suitable for washing with hard water. This is because of the fact that synthetic detergents can lather with hard water. Hence, Synthetic detergents better than soaps.
Synthetic detergents work on both soft and hard water, while soap works only with soft water.
can you please solve this
IMK Your answer is option C
24 protons and 29 neutrons
5 grams of iron react with 5 grams of oxygen to produce iron 3 oxide. If I produce 5 grams of product what is my percent yield?
Answer:
5 grams of iron react with 5 grams of oxygen to produce iron 3 oxide.
The actual yield of the reaction is--- 5 grams.
What is the percent yield?
Explanation:
The balanced chemical equation of the reaction is:
[tex]4Fe(s)+3O_{2} (g)->2Fe_{2} O_3(s)[/tex]
1)Identify the limiting reagent.
2)Using the limiting reagent calculate the amount of theoretical yield formed.
Identification of limiting reagent:
4 mol of Fe reacts with 3mol. of O2
that is:
4mol(55.84g/mol) of Fe reacts with ---- 3mol (32.0g/mol)
=223.36g of Fe reacts with ---- 96g. of O2
then,
5g of Fe requires how many grams of O2?
[tex]=>5g. of Fe * \frac{96g O2}{223.36g Fe} \\=2.14g. of O_{2} .\\[/tex]
But provided 5g of O2.
So, O2 is present more than required.
Hence, O2 is the excess reagent and the limiting reagent is Fe.
The amount of product formed depends only on the amount of Fe only.
Theoretical yield:
From the balanced chemical equation:
4mol. of Fe forms ----- 2mol. of Fe2O3.
that is
223.36g of Fe forms --- 2(159.68g)of Fe2O3.
=>223.36g of Fe forms --- 319.36g of Fe2O3.
then,
5g of Fe forms ----? grams of Fe2O3
[tex]=>5g of Fe * \frac{319.36g Fe2O3}{223.36g of Fe} \\=7.14g. of Fe2O3\\[/tex]
[tex]%Error =\frac{actual yield}{theoretical yield} * 100\\\\ %error=\frac{5g}{7.14g} * 100\\ %error =70.0[/tex]% error=actual yield/ theoretical yield x 100
%error=5g./7.14g x100
=>%error=70.0
Hence, the answer is 70.0%.
What is the role of gravity in maintaining the atmospheric layer around Earth ? Please put a simple explanation Thank you !
Answer:
Explanation:
First of all, we need to understand what gravity is. Gravity in its simplest form can be best visualized as a force of attraction, that pulls all objects that have a mass towards itself.
It is usually exerted by an object with a larger mass and felt by objects with smaller masses.
Putting this into context, the earth exerts a gravitational pull on all substances with masses, which are around it. This includes the oceans, birds, airplanes, clouds, and even gasses in the atmosphere. The atmospheric gasses may be light enough to float, but they can't go very far, since gravity is constantly tugging at them. This keeps the gasses that make up our atmosphere, within a reasonable radius, which is very close to the earth. In a nutshell, gravity prevents them from floating away into outer space.
Students conducted an experiment to determine the relative reactivity of lithium,
magnesium, and zinc metal. They placed a small amount of each metal into separate
beakers of water at room temperature. Choose the order that ranks these metals
according to their relative reactivity with H20, from most reactive to least reactive.
O Li, Mg, Zn
O Li, Zn, Mg
O Mg, Li, Zn
O Zn, Mg, Li
Answer:
Lithium, Magnesium, Zinc
Alpha particles cannot penetrate the skin. In which of the following circumstances could they still threaten human health?
A. If they travel into the human eye.
B. If they are inhaled or swallowed.
C. If they enter into the human ear.
D. If they are touched.
Answer:
B. If they are inhaled or swallowed.
2. Which weather instrument is used to measure wind speed?
gao yin sheng, zhong yin sheng and the other shengs
What is the flow rate of oil if 70mL of oil take 20 seconds to flow out of a pipe?
A ball is thrown straight up into the air with a speed of 13 m/s. If the ball has
a mass of 0.25 kg, how high does the ball go? Acceleration due to gravity is g = 9.8 m/s2
A. 9.2 m
B. 8.6 m
C. 10.4 m
D. 9.9 m
Answer:
The total energy, i.e. sum of kinetic and potential energy, is constant.
i.e. E = KE + PE
Initially, PE = 0 and KE = 1/2 mv^2
At maximum height, velocity=0, thus, KE = 0 and PE = mgh
Since, total energy is constant (KE converts to PE when the ball is rising),
therefore, KE = PE
or, 1/2 mv^2 = mgh
or, h = v^2 /2g = 13^2 / (2x9.8) = 8.622 m
Hope this helps.
A gas has a volume of 1000.0 mL at a temperature of 20.OK and a pressure
of 1.0 atm. What will be the new volume when the temperature is changed
to 40.0K and the pressure is changed to
0.5 atm?
Answer:
4000mL
Explanation:
Using the combined gas law equation;
P1V1/T1 = P2V2/T2
Where;
P1 = initial pressure (atm)
P2 = final pressure (atm)
V1 = initial volume (mL)
V2 = final volume (mL)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the information given in this question:
V1 = 1000mL
T1 = 20K
P1 = 1.0atm
V2 = ?
P2 = 0.5atm
T2 = 40K
Using P1V1/T1 = P2V2/T2
1 × 1000/20 = 0.5 × V2/40
1000/20 = 0.5V2/40
50 = 0.5V2/40
50 × 40 = 0.5V2
2000 = 0.5V2
V2 = 2000/0.5
V2 = 4000mL
Use the table to answer the question
Calculate the average atomic mass of magnesium
A. 24.984 AMU
B. 24.305 AMU
C. 23.985 AMU
D. 25.982 AMU
Answer:
B
Explanation:
hope the picture helps you to understand:)
200 ml of a LiF solution is 5.0M concentration. How many grams of LiF does it have?
Describe the nucleus of an atom in short
Answer:
The nucleus is a small, region at the center of the atom which consists of protons and neutrons.
More Detailed Answer:
The nucleus is a small, dense region at the center of the atom. It consists of positive protons and neutral neutrons, so it has an overall positive charge. The nucleus is just a tiny part of the atom, but it contains virtually all of the atom's mass.
- flexbooks
DIRECTION:Tell how charging takes place in each illustration.
Answer:
Due to static charges.
Explanation:
In the illustration, we can see that when we bring the magnet close to the body, the static charges present on the body rearrange theirselves and attracted by the magnet. The magnetic substance is responsible for the arrangement of charges on the body and when they are arranged, they attract each other so we can say that static charges are present on the body and rearrangement occurs in the body.
Need help asap!
What is the oxidation number of Chromium in Cr2O74-?
There are seven oxygen atoms, so the total charge is −2⋅7=−14 . So, two chromium atoms have a total oxidation number of +12 . Since one is not more electronegative than the other, we can divide the number by two to get one chromium's oxidation number. So, a chromium atom here has an oxidation number of +6 .
Hope it helps you I'm from ph❤️
PLEASE HELP THIS IS AN EMERGENCY!!!!
A template of a Venn diagram representing common and differentiating characteristics of covalent and ionic bonds is shown.
Which of the following characteristics can be written only in space A? (5 points)
A.)Formed between atoms of similar electronegativities
B.)Formed between two metal atoms mostly found on the left of the periodic table
C.)Formed between two non-metal atoms mostly found on the right of the periodic table
D.)Formed between an atom that tends to lose electrons and an atom that tends to gain electrons
Answer:
D
Explanation:
Ionic bonds form when a metal and a nonmetal exchange electrons.
A) atoms with relatively similar electronegativities share electrons between them and form covalent bonds
B) the force that holds atoms together in a metallic substance is known as a metallic bond. such a solid consists of closely packed atoms....in short, the valence electrons in metals, unlike those of covalent bonds, are nonlocalized and capable of wandering relatively freely throughout the entire molecule
C) bonds formed between two nonmetals are mainly covalent bonds
.The characteristic that can be written in A only is that ionic bonds are "formed between an atom that tends to lose electrons and an atom that tends to gain electrons" option D.
Ionic bondIonic or electrovalent bonds are bonds formed between oppositely charged ions which are formed by a gain or loss of electrons and these ions are held together by strong electrostatic forces of attraction.
Properties of Ionic bondsThey are formed between oppositely charged ions ionsThey occur as a result of electrostatic forces of attraction between oppositely charged ions They are formed between an atom that tends to lose electrons {usually metals} and an atom that tends to gain electrons {usually non-metals}.Therefore, characteristic that can be written in A only is that ionic bonds are "formed between an atom that tends to lose electrons and an atom that tends to gain electrons" option D.
Learn more about ionic bonds at: https://brainly.com/question/13526463
Select the correct answer.
Which atom or lon is the largest?
Answer:urenium
Explanation: because his atomic number is 235
Answer:
We know when the no of protons (+ charge) is greater than the no of electrons (- charge), the nucleus pulls the electrons with greater force, hence making the size smaller. Clearly, the cations are smaller than the atoms, this largest atom/ion will be Ca.
K has 19 protons, 19 electrons
K+ has 19 protons, 18 electrons
Ca has 20 protons, 20 electrons
Ca2+ has 20 protons, 18 electrons
Li has 3 protons, 3 electrons
Clearly, the cations are smaller than the atoms, this largest atom/ion will be Ca.
Explanation:
what is Tyndall effect ?
My answer is in the picture.
Hope that helpsStay safe always
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⏩ The scattering of a beam of light through a colloidal solution in its dispersed phase is known as [tex]\large\boxed{tyndall \ \ effect}[/tex].
⁺˚*･༓☾✧.* ☽༓･*˚⁺‧
ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ
꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐
Why do ionic compounds have higher electrical conductivity than molecular compounds?
support your answer with an example.
Answer:
Ionic compounds are formed from strong electrostatic interactions between ions, which result in higher melting points and electrical conductivity compared to covalent compounds. Covalent compounds have bonds where electrons are shared between atoms.
what creates an ionic bond?
a: The attraction between neutral ions
b: The checks between similarly charged ions
c: the attraction between oppositely charged ions
d: the attraction between neutral atoms
Answer:c
Explanation: it’s c
a.
Suppose a group of bobcats that normally live and hunt in the tops of mountains, start hunting prey at the base of the
mountain and move into the valley below. Which of the following will most likely happen to the prey in the valley?
Their numbers will soon increase.
b. Their numbers will soon decrease.
C. They will move to the tops of the mountains.
d. They will remain unchanged.
Please select the best answer from the choices provided
Ο Α
OB
C
OD
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Answer:
University of University of South New York Jersey has is a the best in the world the most important most important aspect of aspect of life is life and marriage is in my a lot more of a urban
What is a prism?
A. Something that measures the energy of light wavelengths
B. Something that raises electrons to higher energy levels
c. Something that combines colors into a single source
D. Something that splits up light into different colors
Answer:
D. Something that splits up light into different colors
Explanation:
A prism separates light into various different colors. Thus, D is correct. :)
The fur on an arctic polar bear appears white all year. The color of the fur is an example of
O A. an organism exchanging materials with its environment
B. an adaptation helping an organism to survive
C. an organism responding to internal stimuli
o D. metabolism regulating an organism's activities
Answer:
It would be B!
Explanation:
Since white fur is a form of camouflage, B would be the correct answer.
How many individual decay steps are in the decay chain of
uranium-238 before the stable end product of lead-206 is
produced?
Answer:
432
Explanation: