Answer:
"How to prevent the collapse of the dam that contains water from heavy rains?"
Explanation:
Scientists must work to create innovations capable of bringing benefits to human life and combating disadvantageous and harmful situations. The overflow of dams is something very harmful, as the resulting flooding can cause structural, economic and even public health problems. When this overflow is caused by natural elements, such as heavy rains, the work of scientists in solving these issues is even more important and necessary. In order to resolve the dam failure caused by excess rainwater, scientists must work to answer the following question:
"How to prevent the collapse of the dam that contains water from heavy rains?"
Question 9 of 10
Which functional group does the molecule below have?
Answer:
Hydroxyl
Explanation:
A P E X
calculate the oxidation number of the central atom of FeSO4 7H2O
Answer:
[tex]{ \tt{let \: the \: oxidation \: state \: be \: x}} \\ { \bf{x + sulphate \: ion+ water = overall \: charge}} \\ \\ \\ { \tt{x + ( - 2) + 0 = 0}} \\ \\ { \tt{x = + 2}} \\ { \tt{oxidation \: state = + 2}}[/tex]
In what way are electrons quantized?
O A. They have fixed energy values.
they
OB. They can be gained and lost.
O C. They are negatively charged.
O D. They form bonds in molecules.
Answer: The correct option is A) They have fixed energy values.
Explanation:
Electron is one of the sub-atomic particle present around the nucleus of an atom which is negatively charged.
In an atomic model, it is assumed that the electron revolves around the nucleus in discrete orbits having fixed energy levels.
These electrons when jumping from one energy level to another, some amount of radiation is either emitted or absorbed.
These fixed energy levels are given by the Bohr model and thus, the electrons are quantized.
Hence, the correct option is A) They have fixed energy values.
Answer: They have fixed energy values
Explanation: a pex
Why does platinum metal make a good catalytic surface for reactant molecules?
It causes reactant molecules to be less reactive.
It strengthens bonds between reactant molecules.
It prevents products from breaking away from the surface.
It holds reactant molecules in a good position for them to react.
Answer:
it holds reactant molecules in a good position for then to react
Answer:
D. It holds reactant molecules in a good position for them to react.
Explanation:
Got a 100 on e2020.
pls answer the following question for me
1. and C.
Terrycot is a fiber that is made by mixing two fibers. Terrycot is a blended fabric made of terylene and cotton. It has better absorbing power as compared to Terylene. Nylon and terylene are produced through condensation polymeriztation.
Hope it helps...
Answer:
Explanation:
1-B
2-A
3-D
4-C
Which of these is a measure of the average kinetic energy of the molecules of a material? A.heat B.temperature C.thermal energy D.bonding energy
Answer:
b temperature
Explanation:
Temperature is a measure of the average kinetic energy of the particles in a substance
NO2 + H2O =
SO2 + H2O =
H2S + H2O=
SO2+ H2O=H2SO3
H2S+ H2O=H2SO4 +H2
NO2+ H2O= HNO3+NO
How do the Carnivorous plants survive without soil?
Answer:
A simple answer: Carnivores don't eat plants only flesh. So they would not need soil. But it would be hard for Carnivores to get energy because they get energy indirectly from the animals (herbivores) that they eat. How do they get the energy from a herbivore you might ask. Herbivores eat only plants and that gives the herbivore the plant's energy; but if the herbivore gets eaten, it is indirectly transferred into the Carnivore. Hope this helped!!
Carnivore = only feeds on flesh
Herbivore = eats only plants
Omnivore = eats plants and animals/flesh
Figure 1 (Use this figure to answer questions 6,7, and 8. Assume that the height at point
A and point C are the same)
С
B
As the car moves from point A, to point B, and finally to point C, the total energy of the car
decreases from point A to point B, then increases from point B to point
increases from point A to point B, then decreases from point B to point
O is lost between points B and C
stays the same, but is converted between potential and kinetic energy
Answer:
JWBVH
Explanation:
NWSBWHSBHS
why is dilute tetraoxosulphate(VI) acid not suitable for preparing carbon monooxide
Answer: Because this does not dissolve in water - it forms a barrier on the surface of the unreacted CaCO3 which prevents any further reaction. A small volume of CO2 is produced , but this stops after a short time . Conclusion: H2SO4 cannot be used with CaCO3 to produce CO2 gas .
Explanation:
help me with this attachment please
Answer:
See explanation
Explanation:
Let us recall that the basic rule in writing balanced chemical reaction equations is that the number of atoms of each element on the right hand side of the reaction equation is the same of the number of atoms of the same element on the left hand side of the reaction equation.
The reaction of red hot iron and steam is written as follows;
3Fe + 4H2O → Fe3O4 + 4H2.
The decomposition reaction of ammonium dichromate is written as;
(NH4)2Cr2O7 → N2 + Cr2O3 + 4H2O
Reaction of aluminium, sodium hydroxide and water is as follows,
2Al + 2NaOH + 2H2O ----> 2NaAlO2 + 3H2
Reaction of potassium bicarbonate with sulphuric acid;
2KHCO3 + H2SO4 -------> K2SO4 + 2H2O + 2CO2
Reaction of zinc and sodium hydroxide is as follows;
Zn + 2NaOH→Na2ZnO2 + H2
4. A piece of metal weighing 0.0713 g was placed in a eudiometer containing dilute aqueous HCl. After the metal fully dissolved, 23.5 mL of hydrogen gas was collected by displace-ment of water and a 400 mm column of water was observed. The water temperature was 258C and the barometric pressure was 758.8 mm Hg (torr). Refer to the Introduction and data sheet to solve the following problems. a) What is the vapor pressure of the water vapor in the column? (Consult Appendix E.)
Complete Question
4. A piece of metal weighing 0.0713 g was placed in a eudiometer containing dilute aqueous HCl. After the metal fully dissolved, 23.5 mL of hydrogen gas was collected by displace-ment of water and a 400 mm column of water was observed. The water temperature was 258C and the barometric pressure was 758.8 mm Hg (torr). Refer to the Introduction and data sheet to solve the following problems.
a) What is the vapor pressure of the water vapor in the column? (Consult Appendix E.)
b) What is the pressure of the water column expressed in mm Hg (torr)? The density of mercury is 13.6 g/mL.
c) Calculate the pressure of the hydrogen gas above the water in the column.
d) Calculate the volume occupied by the hydrogen gas at STP.
Answer:
a) [tex]25\textdegree C=23.8 torrs[/tex]
b) [tex]P_w=758.8[/tex]
c) [tex]P_w=758.8=735torr[/tex]
d) [tex]V_2=20.82mL[/tex]
Explanation:
From the question we are told that:
Metal weight [tex]M_m=0.0713g[/tex]
Volume Hydrogen [tex]V_h=23.5mL[/tex]
Displace-ment Column of water 400 mm column of water
Temperature [tex]T =258\textdegree C[/tex]
Barometric Pressure [tex]p=758.8mmHg[/tex]
Vapour Pressure of water at [tex]25^oC[/tex]
Generally from (Consult Appendix E.)
a)
Va-pour Pressure of water at
[tex]25\textdegree C=23.8 torrs[/tex]
b)
Pressure of Water column
[tex]P_w=758.8[/tex]
c) Pressure of Water column (Consult Appendix E.)
[tex]P_w=758.8=735torr[/tex]
d)
Generally the equation for ideal gas is mathematically given by
[tex]\frac{p_1v_1}{T_1}=\frac{p_2v_2}{T_2}[/tex]
Therefore
[tex]V_2=\frac{p_1V_1T_2}{T_1p_2}[/tex]
[tex]V_2=\frac{735*23.5*273}{298*760}[/tex]
[tex]V_2=20.82mL[/tex]
Será lançado na próxima quarta-feira, 1º de julho, em São Bernardo do Campo (SP), o primeiro ônibus brasileiro a hidrogênio. [...] O projeto Ônibus Brasileiro à Célula Combustível a Hidrogênio é o ponto de partida para o desenvolvimento de uma solução mais limpa para o transporte público urbano no Brasil. (Disponível em: Acesso em: 19 out. 2009.) Quanto aos processos químicos envolvidos na produção de energia elétrica em células de combustíveis a partir do oxigênio e do hidrogênio, é correto afirmar:
Subtract to find the temperature changes
for the water and the metal.
Answer:
???what metal????????????
Which two of the following changes of state involve solids?
Select two (2) answers
A. melting
B. boiling
C. freezing
D. evaporating
Answer:
Answer is A... Melting and freezing
(1) The solubility of Salt AB2(s) is 5mol/dm^3. (a) Obtain an expression for the solubility product of Salt AB2,in terms of s.
Answer:
See explanation
Explanation:
Let the equation of dissolution be;
AB2(s) ⇄A(aq) + 2S
Hence;
Ksp = [A] [2s]^2
Let the concentration of the species be s
Ksp= s × (2s)^2
Ksp= 4s^3
Since s= 5mol/dm^3
Ksp = 4(5mol/dm^3)^3
Ksp = 500 mol^2dm^-6
I have oxygen gas at 2 L and 2 atm. At what pressure is the oxygen gas if my volume decreases to 1 L?
Answer: The oxygen gas has a pressure of 4 atm if my volume decreases to 1 L.
Explanation:
Given: [tex]V_{1}[/tex] = 2 L, [tex]P_{1}[/tex] = 2 atm
[tex]V_{2}[/tex] = 1 L, [tex]P_{2}[/tex] = ?
Formula used to calculate the new pressure is as follows.
[tex]P_{1}V_{1} = P_{2}V_{2}[/tex]
Substitute the values into above formula as follows.
[tex]P_{1}V_{1} = P_{2}V_{2}\\2 atm \times 2 L = P_{2} \times 1 L\\P_{2} = 4 atm[/tex]
Thus, we can conclude that the oxygen gas has a pressure of 4 atm if my volume decreases to 1 L.
An oxygen atom has 8 protons. What number of neutrons would make an
oxygen atom most stable?
A. 10
B. 6
C. 12
D. 8
D. 8
Hope this helps! :)
______________
Answer:
D: 8 neutrons would make it most stable
Why do we need to know these organic molecules?
Are they important to living things?
Answer:
Organic molecules are important to living things because life is based on the properties of carbon.
Properties of Carbon
Carbon is an important element because it can form four covalent bonds.
Carbon skeletons can vary in length, branching, and ring structure.
The carbon skeletons contain the functional groups that are involved in biochemical
Explanation:
Hope it helps
A student wants to make a 0.600 M aqueous solution of barium sulfate, BaSO4, and has a bottle containing 12.00 g of barium sulfate. What should be the final volume of the solution?
Find the numerical answer for this question and make sure to include the following:
What is the formula for molarity?
What is the molar mass for barium sulfate?
When you give your numerical answer, what are the correct significant figures and how do you know that is the correct amount?
Need this ASAP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer: The volume of the solution is 85.7 mL
Explanation:
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
[tex]\text{Molarity of solution}=\frac{\text{Given mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (mL)}}[/tex] .....(1)
We are given:
Molarity of solution = 0.600 M
Given mass of [tex]BaSO_4[/tex] = 12.00 g
We know, molar mass of [tex]BaSO_4=[(1\times 137.33)+(1\times 32.07)+(4\times 16)]=233.4g/mol[/tex]
Putting values in equation 1, we get:
[tex]0.600=\frac{12.00\times 1000}{233.4\times \text{Volume of solution}}\\\\\text{Volume of solution}=\frac{12.00\times 1000}{233.4\times 0.600}=85.68mL=85.7mL[/tex]
The rule of significant number that is applied for the problems having multiplication and division:
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
Here, the least number of significant figures is 3 that is determined by the number, 0.600. Thus, the answer must have these many significant figures only.
Hence, the volume of the solution is 85.7 mL
KHP, the acid used in this experiment,
stands for potassium hydrogen
phosphorous.
True
False
Answer:
false
Explanation:
standard form is Potassium hydrogen phthalate
ChemBonding9. In ammonium chloride NH4Cl, the bonding between NH4+ and chloride ion Cl− is _______.
options:
ionic
polar covalent
nonpolar covalent
State the name(s) of the sub-atomic particle(s) that have/has a positive charge. Answer with the name of the particle(s) only.
A. Neurons
B. Protons
C. Electrons
Answer:
protons because they have the most positive charge
Please I need an explanation on the relationship between concentration and volume of reacting substances
Answer:
when d volume of a substance is high, the concentration is gonna b low...
Jus lyk putting much water in just a cube of sugar
Explanation:
So lower volume, higher concentration
What is the mass of 0.125 moles of tin sulfate (SnSO4)?
Answer:
26.85 grams
Explanation:
The formula for mole calculations is number of moles = given mass/gram-formula mass.
The number of moles is given to us, which is 0.125.
The gram formula mass of SnSO4 is about 214.77.
Plug in the values we have into the equation. It should look like this:
0.125 = x / 214.77
Solve for x by multiplying 214.77 and 0.125. The answer should be about 26.85 grams.
Which group on the periodic table contains chemical elements that are shiny and conduct electricity?
A.
Metalloids
B.
Nonmetals
C.
Representative elements
D.
Metals
A molecule has four bonded atoms around a central atom. The central atom does not have any lone pairs of electrons. What is the geometry of the molecule?
Answer:
Tetrahedral. Tetra- signifies four, and -hedral relates to a face of a solid; “tetrahedral” literally means “having four faces. ” This shape is found when there are four bonds all on one central atom, with no lone electron pairs. In accordance with the VSEPR theory, the bond angles between the electron bonds are 109.5o ...
There are two characteristics of molecules, one is geometry and other is shape. Shape is excluding lone pair surrounding the central element and geometry is including the lone pair. Therefore, the geometry of given molecule is tetrahedral.
What is VSEPR theory?
VSEPR stands for valence shell electron pair repulsions. VSEPR theory is used to predict the shape and geometry of molecules on the basis of valence electrons pairs that are present around the central element of the molecule.
According to VSEPR theory, Lone pair lone pair repulsion is greater than bond pair bond pair repulsion. There are so many limitations of VSEPR theory. There is a repulsion between bond pair electrons and lone pairs present on the central element.
A molecule has four bonded atoms around a central atom. The central atom does not have any lone pairs of electrons. The geometry of such molecule is Tetrahedral. Geometry does not include lone pair on central atom.
Therefore, the geometry of given molecule is tetrahedral.
To know more about VSEPR theory, here:
https://brainly.com/question/19582124
#SPJ6
What is meant by term valency? Explain it in terms of electrons donations and acceptance.
Answer:
Valency can be defined as a measure of the combining power of a chemical element with other atoms to form a molecule or chemical compound.
Explanation:
An atom can be defined as the smallest unit comprising of matter that forms all chemical elements. Thus, atoms are basically the building blocks of matters and as such determines or defines the structure of a chemical element.
Generally, atoms are typically made up of three distinct particles and these are protons, neutrons and electrons.
In Chemistry, electrons can be defined as subatomic particles that are negatively charged and as such has a magnitude of -1.
Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.
Valency can be defined as a measure of the combining power of a chemical element with other atoms to form a molecule or chemical compound.
Typically, valency is measured by the amount of hydrogen atoms that a chemical element can combine with or displace to form a molecule or chemical compound.
For example, Oxygen has a total number of eight (8) electrons while neon has total number of ten (10) electrons. Therefore, an atom of oxygen is able to gain (accept or receive) two (2) more electrons in order to have the same electron arrangements as the noble gas i.e an atom of neon with an atomic number of 10.
Can someone please solve this for me and explain it
83.3% yield
Explanation:
First, we need to convert 240 g of [tex]Fe_{2}O_{3}[/tex] into moles:
[tex]240 \:g \:Fe_{2}O_{3} \:\times(\frac{1\:\text{mol}\:Fe_{2}O_{3}}{159.69\: \text {g}\:Fe_{2}O_{3}})[/tex]
[tex]=1.50 \:\text{mol}\:Fe_{2}O_{3}[/tex]
Next, find the theoretical Fe yield using molar ratios.
[tex]1.50 \: \text {mol} \: Fe_{2}O_{3}\: \times (\frac{2\: \text{mol} \: Fe}{1 \:\text{mol} \: Fe_{2}O_{3}})[/tex]
[tex] = 3.00 \: \text{mol} \: Fe[/tex]
Then convert this back into grams:
[tex]3.00 \: \text{mol} \:Fe \times (\frac{55.845 \: \text{g} \: Fe}{1 \: \text{mol} \: Fe}) = 168 \: \text{g} \: Fe[/tex]
Note that actual yield is only 140 g Fe so percentage yield is
[tex]\dfrac{140\:\text{g}\:Fe}{168\:\text{g}\:Fe} \times 100[/tex]%= 83.3%
83.3%
The answer is 83.3%
BRAINILIEST PLEASEAt 40km up in the atmosphere the pressure is 3.8 kPa. I release a balloon with a volume of 30.0
liters from sea level. The balloon ascends up into to atmosphere 40 km. What will be the new
volume of the balloon, assuming no change in temperature?
Answer in liters
