Answer:
Explanation:
Normal boiling point = 141.7°C
Elevated boiling point = 142.5°C
Elevation of boiling point Δt = 0.8°C
Formula for elevation of boiling point is as follows .
Δt = 1000 x Kb x w / (MW )
where w is weight of solute , M is molecular weight of solute , W is weight of solvent in grams, Kb is molal boiling point elevation constant .
Mol weight of barium hydroxide = 171 .
.8 = 1000 x Kb x 68.1 / (171 x 750 )
Kb = 1.5°C / m
How can you model the cycling of matter in the Earth system?
Answer:
The cycling of matter is important to many Earth processes and to the survival of organisms the existing matter must cycle continuously for this planet to support life Water, carbon, nitrogen, phosphorus, and even rocks move through cycles If these materials did not cycle, Earth could not support life.
Explanation:
Earth activities depend on matter cycling, and for organisms to survive, this planet's surface must cycle with the flow of matter.
What is Earth system?Rocks, as well as water, carbon, nitrogen, and phosphorus, go through cycles. The planet Earth could not support life if these materials did not cycle.
Subsystems exist within the Earth system. These subsystems include the exosphere, atmosphere, hydrosphere, lithosphere and geosphere, also referred to as the lithosphere, and the living environment (biosphere).
These systems are powered by energy that comes from both the Sun and the interior of the Earth. Through processes known as biogeochemical cycles, nutrients and elements also move through these systems along with energy.
Therefore, Earth activities depend on matter cycling, and for organisms to survive, this planet's surface must cycle with the flow of matter.
To learn more about Earth, refer to the link:
https://brainly.com/question/1204146
#SPJ6
I need help with 17,18,19,& 21
Answer:
17. tie hair up
wear goggles
18. i don't know
19. you light it on the side of the box
20. it should be orange because that is the safest.
21. you turn down the electricity thing
helppp nowwww plssssss!!
Set Grouper to 70%. How do you think this level of fishing will affect the populations of the other fish in the simulated reef? Explain your reasoning.
Answer:
Greatly affect.
Explanation:
This level of fishing will greatly affect the populations of the other fish in the simulated reef because overfishing disturbs the equilibrium in the marine ecosystem. One fish is a food of another fish or the big fish act as a controller which controls the population of other small fishes and in that way the ecosystem is present in equilibrium state so overfishing will greatly affect the marine ecosystem.
A cold air mass and a warm air mass are predicted to meet. What type of weather can be expected between the two air masses?
A.
warm weather
B.
cold weather
C.
dry weather
D.
stormy weather
Answer:
Explanation:
C. warm weather
Answer:
stormy weather
6. 7. A hyperbaric chamber has a volume of 200. L. (a) How many moles of oxygen are needed to fill the chamber at room temperature (23°C) and 3.00 atm pressure? b) How many grams of oxygen are needed? (Hint: Since moles have been asked, which equation has the moles listed in the equation. Use that to solve this problem. Also don’t forget to use the equation 1 mole = Formula weight or Molecular weight to calculate the grams of O2).
Answer:
a) 24.7 mol
b) 790 g
Explanation:
Step 1: Given data
Volume of the chamber (V): 200. LRoom temperature (T): 23 °CPressure of the gas (P): 3.00 atmStep 2: Convert "T" to Kelvin
We will use the following expression.
K = °C + 273.15
K = 23°C + 273.15 = 296 K
Step 3: Calculate the moles (n) of oxygen
We will use the ideal gas equation.
P × V = n × R × T
n = P × V/R × T
n = 3.00 atm × 200. L/(0.0821 atm.L/mol.K) × 296 K = 24.7 mol
Step 4: Calculate the mass (m) corresponding to 24.7 moles of oxygen
The molar mass (M) of oxygen ga sis 32.00 g/mol. We will calculate the mass of oxygen using the following expression.
m = n × M
m = 24.7 mol × 32.00 g/mol = 790 g
*SCIENCE*
A nebula contains large amounts of dust and clouds. What role does gravity play inside of nebulae?
0 The gravitational pull between the gas and dusť matter leads to the formation of new galaxies.
0 The gravity pulls the gas and dust apart, leading to the formation of a larger nebula.
0 The gravitational pull between the gas and dust matter leads to the formation of new stars and planets.
0 There is no gravity inside nebulae because each dust particle is so small.
Answer:
The gravitational pull between the gas and dust matter leads to the formation of new galaxies
Explanation:
My teacher went over the answers and said that one was correct.
A nebula contains large amounts of dust and clouds. The gravitational pull between the gas and dusť matter leads to the formation of new galaxies does gravity play inside of nebulae. Therefore, option A is correct.
What is gravity ?Gravity is the force that pulls objects toward the center of a planet or other body. The gravitational force keeps all the planets in orbit around the sun.
Gravity pulls you toward the ground because all objects with mass, such as our Earth, actually bend and curve the fabric of the universe, known as spacetime. Gravity is the curvature of the earth.
A nebula is densely packed with dust and clouds.The gravity play a role inside nebulae, The gravitational pull between gas and dus matter leads to the formation of new galaxies.
Thus, option A is correct.
To learn more about the gravity, follow the link;
https://brainly.com/question/4014727
#SPJ6
Will measuring the melting point of your product tell you that your product is relatively pure?
Answer and Explanation:
Yes. The determination of melting point is used to analyze if a solid compound is pure or impure. The melting point of a pure solid product does not vary in a narrow range, whereas if impurities are present the solid melts in a broad range of temperatures. For this reason, this technique is generally used to determine the identity and purity of the products obtained in chemical reactions.
A student dissolves of aniline in of a solvent with a density of . The student notices that the volume of the solvent does not change when the aniline dissolves in it. Calculate the molarity and molality of the student's solution. Be sure each of your answer entries has the correct number of significant digits.
Answer:
Molarity: 0.21M
Molality: 0.20m
Explanation:
...dissolves 3.9g of aniline (C6H5NH2) in 200.mL of a solvent with a density of 1.05 g/mL...
To solve this question, we need to find the moles of aniline in 3.9g using its molar mass. Then, we need to find the kg and Liters of solution in order to find molarity (Moles/L solution) and molality (Moles/kg of solvent):
Moles aniline:
Molar mass:
6C: 6* 12.01g/mol = 72.06g/mol
7H: 7*1.008g/mol = 7.056g/mol
N: 1*14.007g/mol = 14.007g/mol
72.06g/mol+7.056g/mol+14.007g/mol = 93.123g/mol
Moles of 3.9g: 3.9g * (1mol / 93.123g) = 0.04188moles
Liters solution:
200mL * (1L / 1000mL) = 0.200L
kg solvent:
200mL * (1.05g/mL) * (1kg/1000g) = 0.210L
Molarity:
0.04188mol / 0.200L = 0.21M
Molality:
0.04188mol / 0.210L =0.20m
A sample of a certain organic acid has a mass of 5.000 g. Elemental analysis of this compound found it to contain 1.334 g C, 3.554 g O, and the rest of the mass is hydrogen. If the molar mass of the organic acid is 90.03 g/mol, determine its molecular formula.
Answer:
C₂H₂O₄
Explanation:
Given parameters:
Mass of organic acid = 5g
Mass of C = 1.334g
Mass of O = 3.554g
Mass of H = 5 - (1.334 + 3.554) = 0.112g
Molar mass = 90.03g/mol
Unknown:
Molecular formula of the compound = ?
Solution:
To solve this problem, we find the empirical formula of the compound first. It is the simplest formula of the compound.
Elements C H O
Mass 1.334 0.112 3.554
Molar mass 12 1 16
Number of moles 1.334/12 0.112/1 3.554/16
0.112 0.112 0.222
Divide by the
Smallest 0.112/0.112 0.112/0.112 0.222/0.112
1 1 2
Empirical formula = CHO₂
The molar mass of this empirical formula = 12 + 1 + 2(16) = 45g/mol
Now;
Multiplication index = [tex]\frac{90.03}{45}[/tex] = 2
Molecular formula = (CHO₂)₂ = C₂H₂O₄
what happens to the electrons in a covalent bond?
Answer:
Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outer most (valence) electrons, atoms can fill up their outer electron shell and gain stability.
hope it helps you!!
Mark me as brainlist
For the reaction of ammonia (NH3) with oxygen (O2) to produce water and nitric oxide (NO), how many moles of water are produced when 2.2 moles of ammonia are reacted?
Answer:
3.3 moles of H₂O.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
4NH₃ + 5O₂ —> 6H₂O + 4NO
From the balanced equation above,
4 moles of NH₃ reacted to produce 6 moles of H₂O.
Finally, we shall determine the number of mole of H₂O produced by the reaction of 2.2 moles of NH₃. This can be obtained as follow :
From the balanced equation above,
4 moles of NH₃ reacted to produce 6 moles of H₂O.
Therefore, 2.2 moles of NH₃ will react to produce = (2.2 × 6)/4 = 3.3 moles of H₂O.
Thus, 3.3 moles of H₂O were obtained from the reaction.
Every morning, Jeremiah uses a blender to make a smoothie for breakfast. Which of the
following shows the energy transformation that the blender demonstrates?
А
Electrical - light
B
Chemical → mechanical
с
Mechanical → chemical
D
Electrical mechanical
Answer:
D
Explanation:
Answer:
D: Electrical -> mechanical
Explanation:
Hope this helps!
Indium has a tetragonal unit cell for which the a and c lattice parameters are 0.459 and 0.495 nm, respectively. (a) If the atomic packing factor and atomic radius are 0.693 and 0.1625 nm, respectively, determine the number of atoms in each unit cell. (b) The atomic weight of indium is 114.82 g/mol; compute its theoretical density. (a) Enter your answer for part (a) in accordance to the question statement atoms/unit cell (b) Enter your answer for part (b) in accordance to the question statement g/cm3
Answer:
A) 4 atoms/unit cell
B) 7.31 g/cm^3
Explanation:
A) Determine the number of atoms in each unit cell
attached below is the detailed solution
number of atoms per unit cell ( n ) = 4 atoms/unit cell
B) Given atomic weight of indium = 114.82 g/mol
hence the theoretical density = 7.31 g/cm^3
Attached below is a detailed solution of the question
Name the alkyne. Spelling and punctuation count. A seven carbon chain with a triple bond between carbon 1 and carbon 2. There is a C H 2 C H 2 C H 3 group attached to carbon 3.
Answer: IUPAC name of [tex]CH\equiv C-CH_2-CH_2-CH_2-CH_2-CH_3[/tex] will be hept-1-yne.
Explanation:
The IUPAC nomenclature of organic compounds are given as follows:
1. Select the longest possible carbon chain.
2. For the number of carbon atom, we add prefix as 'meth' for 1, 'eth' for 2, 'prop' for 3, 'but' for 4, 'pent' for 5, 'hex' for 6, 'hept' for 7, 'oct' for 8, 'nona' for 9 and 'deca' for 10.
3. A suffix 'yne' is added at the end of the name if triple bond is present.
[tex]CH\equiv C-CH_2-CH_2-CH_2-CH_2-CH_3[/tex]
The IUPAC name will be hept-1-yne.
BALANCE THAI CHEMICAL EQUATION PLS, help:)
Answer:
4C₈H₄OH + 35O₂ → 32CO₂ + 10H₂O
Explanation:
The unbalanced reaction expression is given as:
C₈H₄OH + O₂ → CO₂ + H₂O
To solve this problem, we use a mathematical approach.
aC₈H₄OH + bO₂ → cCO₂ + dH₂O
Conserving C: 8a = c
H: 5a = 2d
O: a + 2b = 2c + d
Let a = 1, c = 8, d = [tex]\frac{5}{2}[/tex], b = 35
4C₈H₄OH + 35O₂ → 32CO₂ + 10H₂O
Which statement defines the enthalpy of solution?
the total number of particles in a solution
the phase change from a solid to a liquid
o the difference in characteristics between reactants and products
the change in energy when one substance dissolves in another
Answer:
the change in energy when one substance dissolves in another
Explanation:
The enthalpy changes are the heat changes accompanying physical and chemical changes. Actually, an enthalpy change is the difference between the sum of the heat contents of products (final state) and sum of the heat contents of reactants (initial state).
There are basically two types of heat changes that accompanies are reaction which are:
Exothermic changes Endothermic changesTherefore, the change in energy when one substance dissolves in another defines the enthalpy of solution.
Enthalpy of solution is the heat liberated or absorbed when one mole of a substance (solute) is dissolved in a specified volume of solvent (water).
An element has five isotopes. Calculate the atomic mass of this element using the information below. Show all your work. Using the periodic table, identify the element this is likely to be and explain your choice. (18 pts)
A) Isotope 1 – mass: 64 amu; percent abundance: 48.89%
B) Isotope 2 – mass: 66 amu; percent abundance: 27.81%
C) Isotope 3 – mass: 67 amu; percent abundance: 4.11%
D) Isotope 4 – mass: 68 amu; percent abundance: 18.57%
E) Isotope 5 – mass: 70 amu; percent abundance: 0.62%
Answer: Sol:-
Data provided in the question is :-
Atomic mass of isotope -1 = 64 amu
Atomic mass of isotope -2 = 66 amu
Atomic mass of isotope -3 = 67 amu
Atomic mass of isotope -4 = 68 amu
Atomic mass of isotope - 5 = 70 amu
Percentage abundace of isotope - 1 = 48.89 %
Percentage abundance of isotope -2 = 27.81 %
Percentage abundance of isotope - 3 = 4.11%
Percentage abundance of isotope-4 = 18.57%
Percentage abundance of isotope - 5 = 0.62 %
Formula used :-
Average atomic mass of an element =[ {(atomic mass of isotope-1 * percentage abundance of isotope-1) + ( atomic mass of isotope-2 * percentage abundance of isotope -2) + ( atomic mass of isotope -3 * percantege abundance of isotope-3 ) + ( atomic mass of isotope-4 * percentage abundance of isotope-4) + (atomic mass of isotope-5 * percentage abundance of isotope-5)} / 100]
Calculation :-
Put all the value in the formula :-
Average atomic mass of an element = [{(64 * 48.89) + (66 * 27.81) + (67 * 4.11) + (68 * 18.57) + (70 * 0.62)} / 100] amu
= [{(3128.96) + (1835.46) +(257.37) + (1262.76) + (43.4)} / 100] amu
= {(6528.04) / 100} amu
= 65.2804 amu
Average atomic mass of an element is = 65.2804 amu
Then this mass is approximatly equal to atomic mass of zinc so this element would be zinc
atomic mass of zinc = 65.38 \approx 65.2804 amu
Gravity pulls rain and snow down to Earth from the atmosphere through a paire
process called precipitation Water is pulled from elevated areas such as
mountains and hills into lakes, oceans, and water reserviors. What is this
describing?*
role of gravity in the water cycle
role of gravity in condensation
O
role of gravity in evaporation
role of gravity in precipitation
How many formula units of CaO are in 32.7 g of CaO?
Answer:
3.51× 10²³ formula units
Explanation:
Given data:
Mass of CaO = 32.7 g
Number of formula units = ?
Solution:
First of all we will calculate the number of moles.
Number of moles = mass/molar mass
Number of moles = 32.7 g/ 56.1 g/mol
Number of moles = 0.583 mol
Number of formula units:
1 mole = 6.022 × 10²³ formula units
0.583 mol × 6.022 × 10²³ formula units / 1 mol
3.51× 10²³ formula units
The number 6.022 × 10²³ is called Avogadro number.
A tire contains 1.50 mol of air at a gauge pressure of 205 kPa. If the volume of the air in the tire is 0.0120 m3, what is its temperature
Answer:
197.07 K
Explanation:
To solve this problem we can use the PV=nRT equation, where:
P = 205 kPa ⇒ 205 * 0.00986 = 2.02 atmV = 0.0120 m³ ⇒ 0.0120 * 1000 = 12 Ln = 1.50 molR = 0.082 atm·L·mol⁻¹·K⁻¹ T = ?We input the data:
2.02 atm * 12 L = 1.50 mol * 0.082 atm·L·mol⁻¹·K⁻¹ * TAnd solve for T:
T = 197.07 K9. Calculate the specific heat capacity of titanium if a 43.56 g sample absorbs 0.476 kJ as its temperature changes from 20.5 oC to 41.2 oC.
Answer:
c = 0.528 J/g.°C
Explanation:
Given data:
Mass of titanium = 43.56 g
Heat absorbed = 0.476 KJ = 476 j
Initial temperature = 20.5°C
Final temperature = 41.2°C
Specific heat capacity = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 41.2°C - 20.5°C
ΔT = 20.7 °C
476 J = 43.56 g × c × 20.7 °C
476 J = 901.692 g.°C × c
c = 476 J / 901.692 g.°C
c = 0.528 J/g.°C
The diagram below represents the organizational levels of living things.
organisms
organ systems
?
tissues
cells
Which of the following examples represents the missing organizational level?
A blood
B heart
C plasma
D vein
Answer: its vein
Explanation:
Answer: It’s blood
Explanation:
I did the quiz
Magnesium reacts with a silver nitrate solution
The reaction is represented by the ionic equation given
State why this reaction is considered a redox reaction
Answer: Mg oxidised to Mg++ and Ag+ reduced to Ag
Explanation:No ionic equation given!!
assume equation is Mg + 2Ag+ + 2NO3- —> Mg++ + 2Ag + 2NO3-
redox reaction: Ag gains an electron = reduced
Mg loseselectrons = oxidised
In a chemical change
A. materials retain their properties.
B. materials change their properties.
C. new materials do not form.
D. new materials formed are always in liquid form.
Answer:
B. materials change their properties.
Explanation:
In a chemical change, materials often change their properties because a re-arrangement of atoms takes place.
A chemical change is one in which new kind of matter is formed.
It is always accompanied by energy changes.
Chemical changes are not reversible. They lead to the production of new kinds of matter It involves mass changesRequires considerable amount of energyDescribe the relationship between kinetic energy and the states of matter?
PLS HELP I DONT SCIENCE HELP ASAP HELP
Answer:
The kinetic molecular theory of matter states that: Matter is made up of particles that are constantly moving. All particles have energy, but the energy varies depending on the temperature the sample of matter is in. This in turn determines whether the substance exists in the solid, liquid, or gaseous state.
Explanation:
Based on your observations, why do you think the temperature of the NaC2H3O2 solution rose while that of the KCl solution fell
Answer:
Due to exothermic and endothermic reaction.
Explanation:
The temperature of NaC2H3O2 solution rises because exothermic reaction takes place in the solution while on the other hand, the temperature of KCl solution fell because endothermic reaction takes place. In exothermic reaction, heat energy is released to the surrounding whereas in endothermic reaction, heat energy is absorbed from the surrounding so that's why the temperature of one solution increases while the other decreases.
Bond length is the distance between the centers of two bonded atoms. On the potential energy curve, the bond length is the internuclear distance between the two atoms when the potential energy of the system reaches its lowest value. Consider that the atomic radius (sometimes called the covalent or bonding atomic radius) of an element is defined as one-half the distance between the bonded atoms in a homonuclear diatomic molecule. Actual bond lengths in molecules are determined experimentally by such methods as X-ray diffraction and microwave spectroscopy. However, these atomic radii values can be used to give an estimate of the upper limit of bond length in other (heteronuclear) molecules. Given that the atomic radii of H and Br are 37.0 pm and 115 pm , respectively, predict the upper limit of the bond length of the HBr molecule.
Answer:
152 pm
Explanation:
According to the question, we can estimate the bond length from the given values of the atomic radii. This now is the upper limit of the bond length for the molecule.
Since we have that;
Atomic radius of H= 37.0 pm
Atomic radius of Br = 115.0 pm
Bond length = Atomic radius of H + Atomic radius of Br
Bond length = 37.0 pm + 115.0 pm
Bond length = 152 pm
Which of the sets below are not in the order of lowest energy to highest energy: (A. 1s, 2s, 2p, 3s) (B. 2p, 3s, 3p, 4s) (C. 3s, 3p, 4s, 3d) (D. 3s, 3p, 3d, 4s)
Answer:
D
Explanation:
energy level order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s... (as periodic table shows)
Calculate the percent composition (percent by mass of each element) of NH4Cl.
Round to the nearest ONES place ((example: 12.34% = 12%))
Answer:
[tex]\%N=26.2\%\\\\\%H=7.5\%\\\\\%Cl=66.3\%[/tex]
Explanation:
Hello!
In this case, since the calculation of the percent composition of an element in a chemical compound is computing considering its atomic mass, subscript in the formula and molecular mass of the compound it is; for nitrogen, hydrogen and chlorine we have that ammonium chloride has a molar mass of 53.49 g/mol so the percent compositions are:
[tex]\%N=\frac{14.01*1}{53.49}*100\% =26.2\%\\\\\%H=\frac{1.01*4}{53.49}*100\% =7.5\%\\\\\%Cl=\frac{35.45*1}{53.49}*100\% =66.3\%[/tex]
Best regards!