Answer:
d. The sisters played against each other in tennis, but they did it without spite.
Explanation:
Answer:
The sisters played against each other in tennis, but they did it without spite
Explanation:
A certain liquid X has a normal boiling point of 133.60°C and a boiling point elevation constant Kb= 2.46°C kg mol^-1.Calculate the bolling point of a solution made of 52.2g of benzamide (C7H7NO) dissolved in 350. g of X.
Answer:
136.63 °C
Explanation:
ΔTb=Tb solution - Tb pure
Where; Tb pure = 133.60°C
molar mass of solute = 121.14 g/mol
number of moles of solute; 52.2g/121.14 g/mol = 0.431 moles
molality = 0.431 moles/350 * 10^-3 = 1.23 molal
Then;
ΔTb = Kb * m * i
Kb = 2.46°C kg mol^-1
m = 1.23 molal
i = 1
ΔTb = 2.46 * 1.23 * 1
ΔTb = 3.03 °C
Hence;
Tb solution = ΔTb + Tb pure
Tb solution = 3.03 °C + 133.60°C
Tb solution = 136.63 °C
What is the mass of 1.33 moles of Ba3(PO4)2?
Choices:
108 g
801 g
659 g
801 mol
Please help :(
Answer:
801 g
Explanation:
From the question given above, the following data were obtained:
Number of mole of Ba₃(PO₄)₂ = 1.33 moles
Mass of Ba₃(PO₄)₂ =?
Next, we shall determine the molar mass of Ba₃(PO₄)₂. This can be obtained as follow:
Molar mass of Ba₃(PO₄)₂ = (137.3×3) + 2[31 + (4×16)]
= 411.9 + 2[31 + 64]
= 411.9 + 2[95]
= 411.9 + 190
Molar mass of Ba₃(PO₄)₂ = 601.9 g/mol
Finally, we shall determine the mass of Ba₃(PO₄)₂. This can be obtained as follow:
Number of mole of Ba₃(PO₄)₂ = 1.33 moles
Molar mass of Ba₃(PO₄)₂ = 601.9 g/mol
Mass of Ba₃(PO₄)₂ =?
Mole = mass /Molar mass
1.33 = Mass of Ba₃(PO₄)₂ / 601.9
Cross multiply
Mass of Ba₃(PO₄)₂ = 1.33 × 601.9
Mass of Ba₃(PO₄)₂ = 801 g
an orbital is a region in an atom where there is a high probability of finding _________
A) an alpha particle
B) a neutron
C) an electron
D) a positron
Answer:
its electron
Explanation:
i dont have an explanation but i hope you get it right
an oxygen tank used for scuba diving has. avolume of 12.0 L .If the pressure of the tank is known to be 204.047 atm and the temperature is 22.0 C(295 K), how many moles of oxygen are contained in the tank
Answer: 101 moles of oxygen are contained in the tank
Explanation:
According to ideal gas equation:
[tex]PV=nRT[/tex]
P = pressure of gas = 204.047 atm
V = Volume of gas = 12.0 L
n = number of moles = ?
R = gas constant =[tex]0.0821Latm/Kmol[/tex]
T =temperature =[tex]22.0^0C=(22.0+273)K=295K[/tex]
[tex]n=\frac{PV}{RT}[/tex]
[tex]n=\frac{204.047atm\times 12.0L}{0.0821 L atm/K mol\times 295K}=101moles[/tex]
Thus 101 moles of oxygen are contained in the tank
Which feature do all adult echinoderms have?
O moveable spine
O muscular foot
O mantle
O endoskeleton
Answer:
endoskeleton i think
Explanation:
ATOMS
define and describe?
classify it , draw it and label it
how does it relate to your life?
if it didn't exist how would life be different?
Which of these statements is true?
A.The neutrons have a neutral charge and help stabilize an atom
B.The electrons have a negative charge and are in the nucleus
C.The protons have a negative charge and are in the nucleus
D.The electrons have a positive charge and orbit the nucleus in the electron cloud
Answer:
Among these statements B is the correct answer.
What is the relationship between the period number and the number of valence electrons?
Answer: Across each row, or period, of the periodic table, the number of valence electrons in groups 1–2 and 13–18 increases by one from one element to the next. Within each column, or group, of the table, all the elements have the same number of valence electrons.
Relationship between the period number and the number of valence electrons:
There are total 7 period in a periodic table.Valence electrons can be also determined as electrons in the outermost shell.The number of valence electrons in an atom is reflected by its position in the periodic table of the elements.Across each row, or period, of the periodic table, the number of valence electrons in groups 1-2 and 13-18 increases by one from one element to the next.For example: Group 17 has 7 valence electrons which is one less to the next group number i.e. 18.Within each column, or group, of the table, all the elements have the same number of valence electrons.Learn more:
brainly.com/question/371590
The formation of chemical bonds from separated atoms 1. is never spontaneous. 2. increases entropy. 3. is always endothermic. 4. is always exothermic. 5. may be either endothermic or exothermic.
Answer:
is always exothermic
Explanation:
You see, whether a process is endothermic or exothermic depends on the result of the operation; ΔHreaction= ΔHproducts - ΔHreactants.
If the enthalpy of reactants exceeds that of the products, then the process is exothermic.
We should remember that the energy of isolated atoms is always higher than the energy of the compound formed when the atoms bond together. Hence bond making is an exothermic process.
Energy is used to form bonds and released when they are broken, bond-breaking is considered to be endothermic. Additionally, the creation of bonds is typically an exothermic process. The formation of chemical bonds from separated atoms is exothermic. The correct option is 4.
When bonds are created in the products of exothermic processes, more energy is produced than is required to break the bonds between the reactants. The temperature of the reaction mixture rises as a result of exothermic reactions. Endothermic chemical processes are those that generally absorb (or use) energy.
An attraction between atoms or ions is referred to as a chemical bond. Atoms trade or exchange valence electrons to create bonds.
Thus the correct option is 4.
To know more about chemical bonds, visit;
https://brainly.com/question/26997794
#SPJ6
Based on your observations from the glowing splint test with oxygen gas, briefly explain why liquid oxygen is a very hazardous substance
Answer:
liquid oxygen is highly flammable
Explanation:
near any source of heat. liquid oxygen can explode to flames thus being hazardous
What is the density of methane, CH4 in a vessel where the pressure is 910 torr and the temperature is 255 K
Answer: Density of methane is 0.92 g/L
Explanation:
The relation between density and molar mass is :
[tex]d=\frac{PM}{RT}[/tex]
where , d = density
P = pressure = 910 torr = 1.20 atm (760 torr=1atm)
M = molar mass = 16 g/mol ( for methane)
R = gas constant = [tex]0.0821Latm/Kmol[/tex]
T = temperature = 255 K
Putting the values :
[tex]d=\frac{1.20atm\times 16g/mol}{0.0821Latm/Kmol\times 255K}=0.92g/L[/tex]
Thus density of methane is 0.92 g/L
what problems occurs if the firework mixture is not pure(they are dirty or contaminated?
Firework mixture is made up with potassium nitrate and other toxic chemicals. They produce harmful wastes to the atmosphere. If they are contaminated, they make release very dangerous explosives by unwanted reactions.
What are explosives?Explosives are chemicals releasing lot of heat energy to the surrounding upon decomposition. Nitrogen compounds, hydrogen etc are explosive and they will explode in air or water.
Chemicals have to handled carefully and stored as per the conditions based on their chemical and physical properties. Some of them may easily corrode. Some may rapidly reacts with water or air and some may explode in air.
Explosive chemicals causes atmospheric pollution as well as health risk by releasing hazardous chemicals. If they are contaminated then there may occur some unwanted reaction and it will make the risk intense by producing toxic gases.
To find more about explosives, refer here:
https://brainly.com/question/8735140
#SPJ2
How do you think the periodic table helps us better understand our world?
Answer:
The periodic table helps organize all the elements found in the world and tells a great deal of information on each of the elements such as their atomic mass, symbol, atomic number, and more. It even is organized into groups (columns) and periods (rows). The elements in the same group mostly have similar chemical properties. In short, the periodic table is a list of the elements that make up the world around you.
Explanation:
Which of the following subatomic particles gives the nucleus of an atom its mass?
O both protons and neutrons
O electrons only
O neutrons only
O protons only
I really need help with these someone please help me.
3 x 10^4
8 x 10
A student fails to insert the cuvette into the colorimeter or spectrophotometer correctly. What effect will this have on the measured absorbance
Answer:
It would cause scattering of light and absorbance measurement is going to be reported as too large
Explanation:
The curvette was not inserted correctly into the spectrometer. The effect that this would have on measured absorbance is that it would cause scattering of light.
Failing to line the curvette correctly would cause light to scatter, the light reaching the photodetector would be less. This less light would then be interpreted as more light being absorbed. This would end up making the absorbance value to be read as too large.
In an atom, the number of protons equals the number of
nuclei
electrons
neutrons
isotopes
Answer:
Electrons
Explanation:
Which best explains why male whitetail deer grow antlers but females seldom grow antlers?
Answer: I'm not sure if you have a selection of choice but I think it's A. Female deer have no need for antlers.
Explanation: I mean they don't.. Even if the Male are older that doesn't stop a female deer from growing antlers.. Just flimsy one's I guess.
In an ecosystem, as the growth of antlers is controlled by genes male male whitetail deer grow antlers but females seldom grow antlers.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
Learn more about ecosystem,here:
https://brainly.com/question/1673533
#SPJ6
1. Which of the following would be an example of spontaneous
generation?
Answer:
This is the idea of spontaneous generation, an obsolete theory that states that living organisms can originate from inanimate objects. Other common examples of spontaneous generation were that dust creates fleas, maggots arise from rotting meat, and bread or wheat left in a dark corner produces mice
Explanation:
hope you like my answer
Which cause of wildfires is least likely to lead to catastrophic results
O arson
Olightning strike
O controlled burn
O unattended campfire
The controlled burn cause of wildfires is least likely to lead to catastrophic results. Therefore, option (C) is correct.
What is controlled burning?A controlled burn is a fire set intentionally for purposes of forest management, prairie restoration, farming, or greenhouse gas. A controlled burn refers to the intentional burning of slash, fuels through burn piles.
Controlled burning can be done during the cooler months to reduce fuel buildup and reduce the likelihood of serious hotter fires. Controlled burning enhances the germination of desirable forest trees, and exposes soil mineral layers which expand seedling vitality.
Controlled burning is also useful in agriculture as it is often referred to as slash and burns. It is one component of shifting cultivation, as a section of field preparation for planting called field burning. This technique is utilized to clear the land of any existing crop residue and kill weeds and weed seeds.
Field burning is less expensive but because it forms smoke and air pollutants, its use is not common in agricultural areas.
Learn more about controlled burn, here:
https://brainly.com/question/28466648
#SPJ2
Evaluate (754 mm)/(41 s) to three significant figures and express answer in SI units using an appropriate prefix.
1.14m x MG is the answer
what term is best described as the logarithmic measure of the concentration of hydronium ions in a solution
Answer:
pH
Explanation:
We define the pH of a solution as the negative logarithm of hydronium ions concentration in solution.
Thus when we want to define pH mathematically, we write;
pH = - log {H3O^+]
Where;
{H3O^+] means the concentration of hydronium ions in solution.
What is the charge of an element with 15 protons, 19 neutrons and 18 electrons?
Answer:
negative
Explanation:
18 negative
19 neutral
10 positive
there are are more negative
PLZ HELP ME!!!!!! BEING TIMED!!!!!
Answer:
3 one
Explanation:
The process by which cells divide is called
A
O replication
B.
mitosis
C.
respiration
D.
photosynthesis
the answer is mitosis
Britney found an irregularly shaped metal object on the beach that has a mass of 232.5 grams. To determine the volume, she partially filled a cylindrical water bottle and dropped the object in. The water level in the bottle rose by 1.2 cm. The bottle has a diameter of 5 cm. Calculate the density of the metal to determine what type of metal Britney found. Densities, measured in grams per cubic centimeters, g cm3 , for some common metals are listed.
The question is incomplete, the complete question is;
Britney found an irregularly shaped metal object on the beach that
has a mass of 232.5 grams. To determine the volume, she partially
filled a cylindrical water bottle and dropped the object in. The
water level in the bottle rose by 1.2 cm. The bottle has a diameter
of 5 cm. Calculate the density of the metal to determine what type
of metal Britney found. Densities, measured in grams per cubic
centimeter, g
cm3
, for some common metals are listed.
• Copper: 8.86 g
cm3
• Bronze: 9.87 g
cm3
• Silver: 10.5 g
cm3
• Gold: 19.3 g
cm3
Select the word that correctly completes the sentence.
Based on the density of the metal, it is most likely that the metal Britney
found is _______________.
\ copper
\ bronze
\ silver
\ gold
Answer:
Bronze: 9.87 g
bronze
Explanation:
We know that the volume of the liquid = the volume of the object
This is because the object will cause the liquid to occupy its own volume of the container.
Now; area of the container = πr^2 = 3.142 * (5/2)^2 = 19.635 cm^2
Volume of the liquid = volume of the sold = 19.635 cm^2 * 1.2 cm= 23.562cm^3
Now given that;
Density = mass/volume = 232.5 g/23.562cm^3 = 9.87 g/cm^3
what is the correct meaning of the word catapult?
example :
mounting tension between england and the colonies helped catapult washingtons rank in the continental army.
a. hamper
b. improve
c. propel
d. define
Answer:
A. hamper
Explanation:
i did this question before.
Answer:
Improve
Explanation:
They improved Washington's rank so that he could rise to the top.
3 H2 (g) + N2 (g) 2 NH3 (g)
1.36 liters of hydrogen gas will produce how many grams of NH3 at STP?
Answer:
Mass = 0.697 g
Explanation:
Given data:
Volume of hydrogen = 1.36 L
Mass of ammonia produced = ?
Temperature = standard = 273.15 K
Pressure = standard = 1 atm
Solution:
Chemical equation:
3H₂ + N₂ → 2NH₃
First of all we will calculate the number of moles of hydrogen:
PV = nRT
R = general gas constant = 0.0821 atm.L/mol.K
1atm ×1.36 L = n × 0.0821 atm.L/mol.K × 273.15 K
1.36 atm.L = n × 22.43 atm.L/mol
n = 1.36 atm.L / 22.43 atm.L/mol
n = 0.061 mol
Now we will compare the moles of hydrogen and ammonia:
H₂ : NH₃
3 : 2
0.061 : 2/3×0.061 = 0.041
Mass of ammonia:
Mass = number of moles × molar mass
Mass = 0.041 mol × 17 g/mol
Mass = 0.697 g
A scientist wants to make a solution of tribasic sodium phosphate, Na3PO4, for a laboratory experiment. How many grams of Na3PO4 will be needed to produce 725 mL of a solution that has a concentration of Na ions of 1.50 M
Answer:
178.35g
Explanation:
Molarity of a solution can be calculated using the formula:
Molarity = number of moles ÷ volume
Based on the information provided in this question, molarity (M) of the solution = 1.50 M, volume = 725 mL = 725/1000 = 0.725L, n = ?
1.50 = n / 0.725
n = 1.50 × 0.725
n = 1.0875mol
Molar mass of Na3PO4
23(3) + 31 + 16(4)
= 69 + 31 + 64
= 164g/mol
Mole = mass ÷ molar mass
1.0875 = mass/164
mass = 178.35g
On a mission to a newly discovered planet, an astronaut finds gallium abundances of 60.11 % for 69Ga and 39.89 % for 71Ga. What is the atomic mass of gallium for this location
Answer:
69.79
Explanation:
According to this question, Gallium element (Ga) has two isotopes namely: 69Ga and 71Ga respectively.
- Isotope 69Ga contains a percent abundance of 60.11 %, the decimal abundance= 0.6011
- Isotope 71Ga contains a percent abundance of 39.89 %, the decimal abundance = 0.3989
Atomic mass of Ga = (mass of isotope 1 × decimal abundance) + (mass of isotope 2 × decimal abundance)
Atomic mass of Ga = (0.6011 × 69) + (0.3989 × 71)
Atomic mass of Ga = 41.4759 + 28.3219
Atomic mass of Ga = 69.797
Atomic mass of Gallium = 69.79