Answer:
The water supply is not safe.
Explanation:
Ionically, the reaction is;
Pb^2+(aq) + 2Br^-(aq) -------> PbBr2(s)
Amount of Br^- reacted = 2/1000 * 0.12 = 2.4 * 10^-4 moles
From the reaction equation;
1 mole of Pb^2+ requires 2 moles of Br^- for complete precipitation
x moles of Pb^2+ requires 2.4 * 10^-4 moles of Br^-
x = 1 * 2.4 * 10^-4 /2
x = 1.2 * 10^-4 moles of Pb^2+
Concentration of Pb^2+ precipitated from 5ml of tap water = 1.2 * 10^-4 * 1000/5
Concentration = 2.4 * 10^-2 M
The amount of Pb^2+ found in the water is greater than the maximum allowable concentration of Pb2+ ions in water in a local community which is 1.51 x 10-8 M. Therefore, the water supply is not safe.
whats the diffrence beetween fluids and nonfluids
Answer:
One is a fluid and one is not.
Explanation:
Fluid is a common state of certain substances, or a type of matter. Liquid is one of the three phases or state of matter. Fluids flow and has some viscosity (thickness). Liquids also flows and it has volume, but no definite shape. A non fluid is a substance that is not a liquid.
Answer:
one is limited and one isn't
CaO + H2O -> Ca(OH)2
3.50g of Ca(OH)2 was made from 4.20g of CaO? What is the % yield of Ca(OH)2?
The % yield of Ca(OH)₂ : 62.98%
Further eplanationPercent yield is the compare of the amount of product obtained from a reaction with the amount you calculated
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients
Reaction
CaO + H₂O ⇒ Ca(OH)₂
mass CaO= 4.2 g
mol CaO(MW=56,0774 g/mol) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{4.2}{56,0774 g/mol}\\\\mol=0.075[/tex]
mol Ca(OH)₂ based on mol CaO
mol ratio CaO : Ca(OH)₂,= 1 : 1, so mol Ca(OH)₂ = 0.075
mass Ca(OH)₂(MW=74,093 g/mol) ⇒ theoretical
[tex]\tt mass=mol\times MW\\\\mass=0.075\times 74,093 g/mol\\\\mass=5.557~g[/tex]
% yield :
[tex]\tt =\dfrac{actual}{theoretical}\times 100\%\\\\=\dfrac{3.5}{5.557}\times 100\%\\\\=62.98\%[/tex]
An atom has an atomic number of 15 and a mass number of 31. How many protons are there in the atom?
Answer:
No of protons = 15
Explanation:
Given that,
Atomic number = 15
Mass number = 31
We need to find the no of protons in the atom.
We know that,
No of protons = Atomic no of the atom
No of protons = 15
Hence, there are 15 protons in the atoms.
Need help. Is this correct
Answer:
Yes, that is correct!
Explanation:
Answer:
Yes
Explanation:
A covalent bond consists of the mutual sharing of one or more pairs of electrons between two atoms. These electrons are simultaneously attracted by the two atomic nuclei. A covalent bond forms when the difference between the electronegativities of two atoms is too small for an electron transfer to occur to form ions.
Mass Number
19
Atomic Number
Elements
Fluorine
Neon
Aluminium
Phosphorus
10
13
15
a. i. Which of the elements would not be capable of forming compounds
Answer:
Explanation:
The atomic number is the number of protons inside the nucleus of an atom. ... 1.1% carbon 13 with 7 neutrons and a mass of 13.00335 u (measured), and a ... The value given is the mass number of the most stable isotope of that element. ... That's because the chemistry of helium is more like neon (Ne), argon (Ar), etc.
convert 80kg into grams
Answer:
80000 grams
Explanation:
kilo means 1000
80 x 1000 = 80, 000
A student adds 3.00 g of dry ice (solid CO2) to an empty balloon. What will be the volume of the balloon at STP after all the dry ice sublimes (converts to gaseous CO2)?
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Mars
What is the orbit of the Mars?
Is the Sun at the center of the Mars’s orbit?
Describe the motion of Mars throughout its orbit? Does it move at constant speed?
Answer:
Mars has an orbit with a semimajor axis of 1.524 astronomical units (228 million km), and an eccentricity of 0.0934 The planet orbits the Sun in 687 days and travels 9.55 AU in doing so making the average orbital speed 24 km/s.
The eccentricity is greater than that of every other planet except Mercury, and this causes a large difference between the aphelion and perihelion distances—they are 1.6660 and 1.3814 AU
Explanation:
Answer: i hope this helps :)
-- 687 days
-- After years of analysis, Kepler discovered that Mars's orbit was likely to be an ellipse, with the Sun at one of the ellipse's focal points. This, in turn, led to Kepler's discovery that all planets orbit the Sun in elliptical orbits, with the Sun at one of the two focal points.
-- From our point of view as we race around the Sun, Mars is falling behind; consequently, we see Mars moving in a retrograde direction from night to night across the sky. Since the Earth always moves around the Sun faster than Mars, you might imagine that Mars's motion will always be retrograde.
-- Basically, that planets do not move with constant speed along their orbits. Rather, their speed varies so that the line joining the centers of the Sun and the planet sweeps out equal parts of an area in equal times. The point of nearest approach of the planet to the Sun is termed perihelion
How many kilograms is 0.22 lb?
O A. 0.22 kg
O B. 0.454 kg
C. 0.0998 kg
O D. 0.49 kg
Answer:
C)0.0998kg
explanation:
1 POUND=0.453592...kg
Which of these common substances is a mixture?
A Sulfur
B Pure Water
C Spagettios
D Nitrogen
Answer:
D
Explanation:
A is a compound
B is purified water
C is a substance made by two substances
Hope this helps
what is the mass of 1.25 mol of zinc
Answer:
1 mole is equal to 1 moles Zinc, or 65.38 grams.
Explanation:
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Answer:
the color change
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2. For the graph to the left, what is the independent variable? ___
3. For the graph to the left, what is the dependent variable? ___
Answer:
Independent is x, which is the time.
Dependent is y, which is the distance.
Sodium atom with electronic configuration 2,8,1 achieves stable electronic configuration by losing one electron thereby achieving stable electronic configuration of the nearest Noble gas
(argon/ neon/ helium).
51 liters of helium and 29 liters of oxygen (O2), both at 35°C and 1.0
atmosphere, are pumped into a tank that has a volume of 5 liters. Calculate the number
of moles of each component and the total pressure in the tank at 35°C
Answer:
If I have an unknown quantity of gas at a pressure of 1.2 atm, a volume of 31 liters, ... If I contain 3.0 moles of gas in a container with a volume of 60. liters and at a ... Mixtures of helium and oxygen are used in scuba diving tanks to help prevent ... volume of 5.00 Lat 25.0C. Calculate the partial pressure of each gas and the ...
Explanation:
What do you think causes a lunar eclipse? (Use your knowledge of solar eclipses and feel free to run the Gizmo to help you.)
Moon reflects the light frim the sun, thats why we are able to see it and it shines in the night. But, we know that Earth revolves around Sun and Moon revolves around Earth. During this revolution, Earth and Moon comes in a position when Earth is in the middle of the Moon and Sun. So, it blocks the light of Sun frim reaching Moon. Hence, we see no reflection and it causes Lunar eclipse.
Answer:
A total lunar eclipse occurs when the moon and the sun are on exact opposite sides of Earth. Although the moon is in Earth's shadow, some sunlight reaches the moon. The sunlight passes through Earth's atmosphere, which causes Earth's atmosphere to filter out most of the blue light.
Explanation:
How many chlorine atoms are on the products side of the reaction 2 Li +
MgCl2 → 2 LiCl + Mg?*
Answer:
2 chlorine atoms on the product side.
Which of the following best represents and explains the formula for a compound made from fluorine and hydrogen?
A. HF, because both fluorine and hydrogen are capable of forming only one ionic bond.
B. HF, because both fluorine and hydrogen are capable of forming only one covalent bond.
C. H2F, because fluorine is short of two electrons, and hydrogen is short of one electron.
D. H2F, because fluorine is capable of forming one, and hydrogen is capable of forming two covalent bonds.
Thank you
The answer is B
HF, because both fluorine and hydrogen are capable of forming only one covalent bond.
The formula for a compound made from fluorine and hydrogen is HF, because both fluorine and hydrogen are capable of forming only one covalent bond. The correct option is option B.
What is chemical Compound?Chemical Compound is a combination of molecule, Molecule forms by combination of element and element forms by combination of atoms in fixed proportion. Covalent bond is weaker than ionic bond.
There are two types of chemical compound one is covalent compound and other is ionic compound, covalent compound formed by sharing of electron and ionic compound formed by complete transfer of electron.
The formula for a compound made from fluorine and hydrogen is HF, because both fluorine and hydrogen are capable of forming only one covalent bond.
Therefore, the correct option is option B.
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what volume of water has a mass of 1 kg
Answer:
[tex]V=0.001\ m^3[/tex]
Explanation:
Mass, m = 1 kg
The density of water, d = 1000 kg/m³
We need to find the volume of water. The formula for the density of an object is equal to mass divided by volume. Its formula is :
d = m/V
V is the volume of water
[tex]V=\dfrac{m}{d}\\\\V=\dfrac{1\ kg}{1000\ kg/m^3}\\\\=0.001\ m^3[/tex]
So, the volume of water is [tex]0.001\ m^3[/tex].
Answer:
Volume of water has a mass of 1 kg is explained below in details.
Explanation:
One liter of h2O has a volume of approximately specifically one kilogram when estimated at its maximum frequency, which happens at about 4 °C. It observes, therefore, that thousand of a liter, recognized as one milliliter (1 mL), of h2O has a volume of about 1 g; 1000 liters of h2O has a volume of about 1000 kg (1 tonne).
1. If you need to name the alkane C7H16, which prefix and
suffix do you use? What sort of meaning do those prefix and
suffix convey?
The name is heptane. The prefix is hept- , because the longest carbon chain contains seven carbons. The suffix is -ane, because this is the suffix used for all alkanes.
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She remembered that chemical equations can summarize what happens in a chemical reaction. What is the name of the two parts found on the left side of the equation below? 4 Fe + 3O2 → 2Fe2O3 A. products B. reactants C. scientific notation D. synthesis
Answer:
The name of the two parts found on the left side of the equation is reactants.
Explanation:
Chemical reaction is the way one substance reacts against another. That is, a chemical reaction is that chemical process in which two or more substances, by the action of an energy factor, are converted into other substances. The new substance (s) that are formed usually present a totally different appearance from that of the starting substances.
In a chemical reaction there are the substances that react, that is, the reactants, and the substances produced, called products.
A chemical reaction is represented by a chemical equation. The formulas of the reactants are written on the left, and those of the products on the right, both separated by an arrow indicating the direction of the reaction.
Reactants ⇒ Products
Then, the name of the two parts found on the left side of the equation is reactants.
Is it possible for two different compounds to be made from the exact same two elements? Why or why not? With a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?
PLEASE HELP ASAP
Thank you!!
Answer:
Yes. The two elements can combine to form different compounds.
Explanation:
Two elements can combine at different ratios.
Consider CO and CO₂. Both are made from carbon and oxygen. However, C and O combine at a 1:1 ratio in CO but at a 1:2 ratio in CO₂. CO is a fuel; it burns in the air. CO₂ does not burn in the air; it is used to put out fires and is found in extinguishers. CO and CO₂ are two distinct compounds.
There are many ways for the elements to combine with each other. As a result, the first twenty elements on the periodic table alone can produce a large number of compounds.
which type of stress causes rocks to fold?
A.) compression
B.) shearing
C.) strike-slip-
D.) tension
Answer:
A. compression
Explanation:
the rock is unable to move causing it to stress
Answer: a. Compression
Mu Cephei is no longer considered a main sequnce star. This means it has run out of:
A:hydrogen
B:Helium
C:Oxygen
D:Iron
Answer:
A: Hydrogen
Explanation:
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Answer:
3 times ....
group 2
Explanation:
Which of the following molecules has a central atom with precisely two unshared
pairs of electrons?
How would I fill out this chart?
Answer:
[Top row] - Chemical bonds
[2nd Row L-R] - Force, Ionic, Covalent
[3rd Row L-R] - Atoms, Lost or Gained, Shared
[4th Row L-R] - More stable, Metal and Nonmetal, Nonmetal and Nonmetal
Explanation:
Chemical bonds are a force that hold together atoms in a substance to make compounds more stable.
Chemical bonds include two kinds: Ionic and Covalent.
Ionic in which electrons are lost or gained where attraction is between a Metal and Nonmetal.
Covalent in which electrons are shared where attraction is between a nonmetal and nonmetal.
I have been able to fill the concept map using the correct terms or phrases. The concept map talks about chemical bonds. There are two types of chemical bonds; which ionic bond and covalent bond.
1. Two substances, both solids, start at the same temperature. You transfer
the same amount of energy into both solids, but substance 1 becomes a
liquid before substance 2. Which substance has a stronger molecular
attraction?
A Substance 1
B Substance 2
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Answer:
B substance 2
Explanation:
1. Two substances, both solids, start at the same temperature. You transfer
the same amount of energy into both solids, but substance 1 becomes a
liquid before substance 2. Which substance has a stronger molecular
attraction?
A Substance 1
B Substance 2
Please help I will give you Brainlyest
Substance 2 has a stronger molecular attraction.
What are solids?Solid is one of the four fundamental states of matter. The molecules in a solid are closely packed together and contain the least amount of kinetic energy. A solid is characterized by structural rigidity and resistance to a force applied to the surface.
Both solids are supplied with an equal amount of energy. Out of both substances, substance 2 has a stronger molecular attraction due to which it can not easily change into a liquid while substance 1 has a lesser molecular attraction so supplying of few amounts of heat will change substance 1 into a liquid state.
Hence, Substance 2 has a stronger molecular attraction.
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1. In which area are you most likely to find plants that can tolerate water that has a constantly
changing salt content?
A. a freshwater stream
B. an estuary
C. a a pond
D. a coral reef
Answer:
I would think B, an estuary. But I'm not sure.
Explanation:
The area where the plants should be find in which the water should be tolerated should be estuary.
What is an estuary?An estuary refer to the enclosed body with respect to the brackish water that have one or more rivers or streams that should be flow into it. Also, there should be free connection to the open sea. It should be considered as the transition zone that lies between the river environment and maritime environment
Therefore, we can conclude that the option b is correct.
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Please help me label this.
Answer:
+ - protons
the green one- nutrons
black ones- electron
the rings are the energy level
The middle layer is the nucules
