Why are measurements important for science?
Pleaseee help me :( give two reasons why it's important
Answer:
measurements are important to do calculations to get correct results and without them scientists cannot form theories
The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction _____.
alculating Displacement under Constant Acceleration
Use the information from the graph to answer the
question
What is the total displacement of the object?
m
Velocity vs. Time
40
30
Velocity (m/s)
20
10
0
0
5
10
15
20
25
Time (s)
Intro
Done
ODO
ODDO
tivity
Answer:
[tex]10 {7}^{2} = [/tex]
Among the given solutions of potassium permanganate (KMnO4), which one has the highest concentration of water in it?
Answer: Solution D has the highest concentration of all.
Explanation:
The formula used to calculate molarity:
[tex]\text{Molarity of solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution (mL)}}[/tex] .....(1)
For A:Molarity of permanganate solution = 0.1 M
Volume of solution = [tex]100 cm^3=100mL[/tex] (Conversion factor: [tex]1mL=1cm^3[/tex])
Putting values in equation 1, we get:
[tex]0.1=\frac{\text{Moles of permanganate solution}\times 1000}{100}\\\\\text{Moles of permanganate solution}=\frac{100\times 0.1}{1000}=0.01mol[/tex]
For B:Molarity of permanganate solution = 0.01 M
Volume of solution = [tex]100 cm^3=100mL[/tex]
Putting values in equation 1, we get:
[tex]0.01=\frac{\text{Moles of permanganate solution}\times 1000}{100}\\\\\text{Moles of permanganate solution}=\frac{100\times 0.01}{1000}=0.001mol[/tex]
For C:Molarity of permanganate solution = 2 M
Volume of solution = [tex]100 cm^3=100mL[/tex]
Putting values in equation 1, we get:
[tex]2=\frac{\text{Moles of permanganate solution}\times 1000}{100}\\\\\text{Moles of permanganate solution}=\frac{100\times 2}{1000}=0.2mol[/tex]
For D:Molarity of permanganate solution = 2.5 M
Volume of solution = [tex]100 cm^3=100mL[/tex]
Putting values in equation 1, we get:
[tex]2.5=\frac{\text{Moles of permanganate solution}\times 1000}{100}\\\\\text{Moles of permanganate solution}=\frac{100\times 2.5}{1000}=0.25mol[/tex]
The solution having the highest number of moles will have the highest concentration for the same volume.
Thus, solution D has the highest concentration of all.
 Help ASAP only right answers only no spam don’t answer if you don’t know
…..
Answer:
Inference
Explanation:
I mean, it's not difficult.
A theory is an unproven explanation.
An inference is a guess/educated guess where you don't have all the facts.
For example, if "Bob" is caught in the kitchen with a ketchup stain on his shirt, you are inferencing that he used the ketchup.
However, if you see a ketchup bottle nearby or saw it earlier, then it is not, because you already have the facts that ketchup was used.
Calculate the average atomic mass for element X(please help)
Answer:
Wt Avg At Mass = 39.0229 amu
Explanation:
The Weight Average Atomic Mass in atomic mass units (amu) is the sum of the Weight Average Mass contributions of each isotopic mass. That is,
Wt. Avg. At. Mass (amu) = ∑ Wt. Avg. Contributions of each isotopic mass
Wt. Avg. Contribution = fractional abundance x isotopic mass(amu)
For this problem data:
Isotope %Abundance fractional Isotopic Wt Avg Isotopic
abundance mass(amu) Contribution (amu)
1 9.67% 0.0967 38 3.6746 amu
2 78.68% 0.7868 39 30.6852 amu
3 11.34% 0.1134 40 4.5360 amu
4 0.31% 0.0031 41 0.1271 amu
________________________________________________________
Wt. Avg. Atomic Mass (amu) = ∑ Wt. Avg. Contributions = 39.0229 amu
Nitrogen dioxide, a major air pollutant, can be produced by the combustion of nitrogen oxide as shown. 2NO + O2 Right arrow. 2NO2 In a plant, 1,500 kg of nitrogen oxide is consumed per day to produce 1,500 kg of nitrogen dioxide per day. What is the percent yield? Use Percent yield equals StartFraction actual yield over theoretical yield EndFraction times 100.. 21.7% 32.6% 43.5% 65.2% Mark this and return Save and Exit Next Submit
Answer:
65.2%
Explanation:
It is given that :
[tex]$2NO + O_2 \rightarrow 2NO_2$[/tex]
Therefore, 60 g of nitrogen oxide will produce 92 g of nitrogen dioxide
or 60 kg of nitrogen oxide will produce 92 kg of nitrogen dioxide
or 1500 kg of nitrogen oxide will produce [tex]2300\ kg[/tex] of nitrogen dioxide
Therefore the percentage yield = (Actual yield / Expected yield) x 100
percentage yield = [tex]$\frac{1500}{2300} \times 100$[/tex]
Percentage yield = 65.217 %
Answer:
the person above me is correct, the answer for this is 65.2% or option D!
Explanation:
thank you person above me! i got a 100% on the test! :D
Atoms are:
O A. One of the 4 elements that matter is composed of.
B. Connected by bonds to form compounds.
OC. The basic building blocks of matter.
O D. Heterogeneous and refer to color, texture, and appearance.
Reset Selection
Answer:c
Explanation: atoms make matter
Atoms are the basic building blocks of matter. The correct option is C.
What are atoms?Atoms are the basic unit and building block of matter. They are the smallest unit, but they can be divided. They do not emit charge on dividing into the further, the smallest parts.
Atoms are further divided into electrons, protons, and neutrons. They are the charged particles that revolve in the shell of the atom. A nucleus is also present in the between of the atom.
Atoms are considered the building blocks of matter, as all matter is made up of many atoms. The configuration of the atom defines the state of matter.
Thus, the correct option is C. The basic building blocks of matter.
To learn more about atoms, refer to the link:
https://brainly.com/question/1566330
#SPJ5
How many moles of atoms does H2O
different oil refineries in UAE
Answer:
Petroleum refinery capacity in the UAE 2009-2018
In 2018, the total production capacities of all refineries in the UAE were 1.13 metric barrels per day. Total total production capacity of the al-Ruwais refinery in the United Arab Emirates was approximately 817,000 metric barrels per day.
What is the name of the process manufacturers use to make unsaturated fatty acids more solid at room temperature and prevent oxidation.
Answer:
Hydrogenation
Explanation:
Look up the definition to confirm
40 POINTS! WILL MARK BRAINLIEST!! Determine the mass in grams of 4.83 × 10²¹ atoms of arsenic. (The mass of one mole of arsenic is 74.92 g.)
Answer:
[tex]\boxed {\boxed {\sf 0.601 \ g \ As}}[/tex]
Explanation:
We want to convert atoms of arsenic to mass in grams. We have to complete 3 steps.
1. Convert Atoms to MolesThe first step is converting atoms to moles. We use Avogadro's Number for this. This number is 6.022*10²³ and it is the number of representative units (molecules, atoms, etc.) in 1 mole of a substance. In this problem, the particles are atoms of arsenic. So, 1 mole of arsenic contains 6.022*10²³ atoms of arsenic. Use this information to make a ratio.
[tex]\frac{1 \ mol \ As}{{6.022*10^{23} \ atoms \ As} }[/tex]
Multiply by the number of atoms provided in the problem: 4.83 × 10²¹
[tex]4.83 *10^{21} \ atoms \ As *\frac{1 \ mol \ As}{{6.022*10^{23} \ atoms \ As} }[/tex]
The units of atoms of arsenic (atoms As) cancel.
[tex]4.83 *10^{21} *\frac{1 \ mol \ As}{{6.022*10^{23}} }[/tex]
Condense into 1 fraction.
[tex]\frac{4.83 *10^{21} }{{6.022*10^{23}} } \ mol \ As[/tex]
[tex]0.008020591166 \ mol \ As[/tex]
2. Convert Moles to GramsThe next step is converting moles to grams. We use the molar mass for this, which is provided. There are 74.92 grams of arsenic in 1 mole of arsenic, so we can make another ratio.
[tex]\frac {74.92 \ g\ As}{ 1 \ mol \ As}[/tex]
Multiply by the number of moles we calculated.
[tex]0.008020591166 \ mol \ As*\frac {74.92 \ g\ As}{ 1 \ mol \ As}[/tex]
The units of moles of arsenic (mol As) cancel.
[tex]0.008020591166 *\frac {74.92 \ g\ As}{ 1}[/tex]
[tex]0.6009026901 \ g \ As[/tex]
3. RoundThe original measurement of atoms (4.83 × 10²¹ ) has 3 significant figures, so our answer must have the same.
For the number we calculated, that is the thousandth place. The 9 in the ten-thousandth place (0.6009026901) tells us to round the 0 to a 1.
[tex]0.601 \ g \ As[/tex]
There are approximately 0.601 grams of arsenic.
what is the application of chemistry
Answer:
Chemistry plays an important and useful role towards the development and growth of a number of industries. This includes industries like glass, cement, paper, textile, leather, dye etc. We also see huge applications of chemistry in industries like paints, pigments, petroleum, sugar, plastics, Pharmaceuticals.
The ground state of an electron is the least stable energy state of an atom
Answer:
electron configuration
Explanation:
The arrangement of electrons in the atomic orbitals of an atom is called the electron configuration. Electron configurations can be determined using a periodic table.
Explain specifically how an electron gives off light in an atom.
Answer:
Then, at some point, these higher energy electrons give up their "extra" energy in the form of a photon of light, and fall back down to their original energy level.
Explanation:
When properly stimulated, electrons in these materials move from a lower level of energy up to a higher level of energy and occupy a different orbital.
Solubility of which salts does not dependent on temperature.Any three.
Answer:
any salt
sodium chloride
callcium chloride
potassium chloride
Explanation:
There is no general effect of temperature on the solubility of salts.effect of increase temperature on the solubilty of NaCl is not significant because it is more soluble even at low temperature. The salt like potassium iodide (KI) has negative heat of solution so it's solubility decreases with increase of temperature…
8. A saturated solution of Ag Croq has a silver-ion concentration of 1.3 x 10-4M. Which is the Ksp of Ag CrO 4?
O 1.3 x 10-4
O 3.9 x 10-12
O 6.5 x 10-5
O 1.1 x 10-12
Answer: The [tex]K_{sp}[/tex] of [tex]AgCrO_{4}[/tex] is [tex]1.1 \times 10^{-12}[/tex].
Explanation:
Given: [tex][Ag^{+}] = 1.3 \times 10^{-4} M[/tex]
The reaction equation will be written as follows.
[tex]Ag_{2}CrO_{4} \rightleftharpoons 2Ag^{+} + CrO^{2-}_{4}[/tex]
This shows that the concentration of [tex]CrO^{2-}_{4}[/tex] is half the concentration of [tex]Ag^{+}[/tex] ion. So,
[tex][CrO^{2-}_{4}] = \frac{1.3 \times 10^{-4}}{2}\\= 0.65 \times 10^{-4} M[/tex]
The expression for [tex]K_{sp}[/tex] of this reaction is as follows.
[tex]K_{sp} = [Ag^{+}]^{2}[CrO^{2-}_{4}][/tex]
Substitute values into the above expression as follows.
[tex]K_{sp} = [Ag^{+}]^{2}[CrO^{2-}_{4}]\\= (1.3 \times 10^{-4})^{2} \times 0.65 \times 10^{-4}\\= 1.1 \times 10^{-12}[/tex]
Thus, we can conclude that the [tex]K_{sp}[/tex] of [tex]AgCrO_{4}[/tex] is [tex]1.1 \times 10^{-12}[/tex].
What mss of sulfamic acid is required to make 250cm3 of a 0.150mol/dm3 solution? please help
Answer:
sorry i dint understand can u ask it in a simpler way
Explanation:
What is the difference between an orbit in the Bohr model of the hydrogen atom and an orbital in the quantum mechanical model
Answer:
See explanation
Explanation:
In Bohr's theory, electrons are found in specific regions in space called orbits. These orbits are also called energy levels. An electron may move from one energy level to another by absorbing or emitting energy.
In the wave mechanical model, electrons are not found in a particular region in space according to Heisenberg's uncertainty principle.
We rather define a certain region in space where there is a high probability of locating the electron. This region in space where there is a high probability of locating the electron is called an orbital.
Hence, in the Bohr's model of the atom,electrons can surely be found in orbits while in the wave mechanical model, the orbital is a probability function that describes a region in space where an electron may be found.
Help ASAP only right answers only no spam don’t answer if you don’t know
Answer: Solve problems
How many molecular of H2O and O2 are present in 8.5g of H2O2 ?
2H2O+O2--->2H2O2
8.5 gm H2O2=0.25 mole
hence H2O is also 0.25 mole i.e.4.5 gm
O2is 0.125 mole i.e.4 gm
3. If there were multiple products comment on finding the mixture melting point of the products. Does your sample appear to be a mixture or pure
Answer:
If there were multiple products, we can take each product and mixed with a sample of a pure compound that we suspect might be the same as the product. Then, we taking the melting point of this mixture that contains one of our product and pure sample. Then, we can observe the change in melting point, if there is no change in melting point or the melting stays in the same range of the pure compound. Then, the that product along with the pure sample are actually the same compound, not a mixture of two compounds. However, if the melting point for our pure sample compound changed or didn't stay in the same range after the mixing with on of our products. then we can conclude that this product and the pure sample are completely different compound, and indeed they are a mixture.
El fluoruro de hidrógeno HF que se utiliza en
la obtención de los freones (los cuales
destruyen la capa de ozono de la
estratosfera), se prepara mediante la
siguiente reacción: CaF2 + H2SO4
CaSO4 + 2HF Si se hacen reaccionar 50gr
de CaF2 con 100 gr de H2SO4 (masas
atómicas Ca=40,F=19, H=1, S=32, O=16)
Answer:
25.6g de HF son producidos
Explanation:
...¿Cuánto HF es producido?
Para resolver este problema debemos convertir la masa de cada reactivo a moles usando su masa molar. Como la reacción es 1:1, el reactivo con menor número de moles es el reactivo limitante. Con las moles del reactivo limitante podemos obtener las moles de HF y su masa así:
Moles CaF2:
Masa molar:
1Ca = 40g/mol
2F = 19*2 = 38g/mol
40+38 = 78g/mol
50g CaF2 * (1mol/78g) = 0.641 moles CaF2
Moles H2SO4:
Masa molar:
2H = 2g/mol
1S = 32g/mol
4O = 64g/mol
98g/mol
100g H2SO4 * (1mol / 98g) = 1.02 moles H2SO4
Como las moles de CaF2 < Moles H2SO4: CaF2 es reactivo limitante.
Moles HF usando la reacción:
0.641 moles CaF2 * (2mol HF / 1mol CaF2) = 1.282 moles HF
Masa HF:
Masa molar:
1g/mol + 19g/mol = 20g/mol
1.282 moles HF * (20g/mol) =
25.6g de HF son producidos.......................
...
....................................
what is chemical reaction?
Answer:
a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction.
Or
Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. ... A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
A 4.369 g sample of metal is placed in a flask. Water is added to the flask and the total volume in the flask is read to be 126.4 ml. The mass of the water, flask, and metal is 268.5 g. If the mass of the flask is 139.3 g and the density of water is 1.000 g/mL, the density of the solid is ________ g/cm3.
Answer:
Density of the solid=[tex]2.78 g/cm^3[/tex]
Explanation:
We are given that
Mass of sample of metal=4.369 g
Volume in the flask, V=126.4 ml
Mass of water, flask, and metal=268.5 g
Mass of flask=139.3 g
Density of water=1.000 g/mL
We have to find the density of the solid.
Mass of water=268.5-4.369-139.3=124.831 g
Volume of water=[tex]\frac{Mass\;of\;water}{density\;of\;water}[/tex]
Volume of water=[tex]\frac{124.831}{1}=124.831 mL[/tex]
Volume of solid=126.4 ml-124.831 mL
=1.569mL
Now,
Density of the solid=[tex]\frac{mass\;of\;solid}{volume\;of\;solid}[/tex]
=[tex]\frac{4.369}{1.569}[/tex]
[tex]=2.78g/mL[/tex]
1mL=1 cubic cm
Therefore,
Density of the solid=[tex]2.78 g/cm^3[/tex]
Aluminum hydroxide, with heat, creates__
Which of the following
Combination,decomposition,
Single replacement,
Double replacement,
Combustion
Answer: Decomposition is the answer
Explanation: why because aluminium hydroxide would decomposes in the presence of heat and would form an oxide which is aluminium oxide and would also form water as a product.
HOPE THIS HELPS!!
Someone plz help me here are the photos, I need the last one
Answer:
(6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol) - (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)
Explanation:
Question; From the given options, the chemical reaction in the question is presented as follows;
C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l), given that we have;
[tex]\Delta \text H _f^{\circ}[/tex] for C₆H₁₂O₆ = -1,273.02 kJ/mol
[tex]\Delta \text H _f^{\circ}[/tex] for O₂(g) = 0 kJ/mol
[tex]\Delta \text H _f^{\circ}[/tex] for CO₂(g) = -393.5 kJ/mol
[tex]\Delta \text H _f^{\circ}[/tex] for H₂O(l) = -285.83 kJ/mol
The heat or enthalpy of a reaction, is given as follows;
[tex]\Delta\text H_{rxn}^{\circ} = \sum \text n \cdot \Delta \text H _f^{\circ}(\text {products}) - \sum \text m \cdot \Delta \text H _f^{\circ}(\text {reactants} \text)[/tex]
Therefore, the equation which should be used to calculate [tex]\Delta\text H_{rxn}^{\circ}[/tex], is given as follows;
[tex]\sum \text n \cdot \Delta \text H _f^{\circ}(\text {products})[/tex] = (6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol)
[tex]\sum \text m \cdot \Delta \text H _f^{\circ}(\text {reactants} \text)[/tex] = (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)
Therefore;
[tex]\Delta\text H_{rxn}^{\circ}[/tex] = (6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol) - (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)
Why Should a magnesium ribbon be cleaned before burning ?
A magnesium ribbon is cleaned to remove the protective layer of basic magnesium carbonate from its surface, so that it may readily combine with the oxygen in air (on heating).
Answer:
Magnesium gets covered with a layer of magnesium oxide when kept in air for a long time. This layer hinders the burning of magnesium. Hence, it is to be cleaned before burning.
How are carbon-based molecules suited for sustaining life?
[tex]\huge\fcolorbox{red}{pink}{Answer ♥}[/tex]
Life on Earth is based on carbon, likely because each carbon atom can form bonds with up to four other atoms simultaneously. This quality makes carbon well-suited to form the long chains of molecules that serve as the basis for life as we know it, such as proteins and DNA.
Hope it helps uh ✌️✌️✌️
