Explanation:
According to the law of conservation of mass, mass can neither be created nor destroyed but it can simply be transformed from one form to another.
For example, [tex]Na^{+} + Cl^{-} \rightarrow NaCl[/tex]
Mass of Na = 23 g/mol
Mass of Cl = 35.5 g/mol
Sum of mass of reactants = mass of Na + mass of Cl
= 23 + 35.5 g/mol
= 58.5 g/mol
Mass of product formed is as follows.
Mass of NaCl = mass of Na + mass of Cl
= (23 g/mol + 35.5) g/mol
= 58.5 g/mol
As mass reacted is equal to the amount of mass formed. This shows that mass is conserved.
As a result, law of conservation of mass is obeyed.
Question: How do we read chemical formulas?
Any molecule can be represented by a formula that lists all the atoms in that molecule. Each element is represented by its atomic symbol in the Periodic Table – e.g. H for hydrogen, Ca for calcium. If more than one atom of a particular element is present, then it’s indicated by a number in subscript after the atomic symbol — for example, H2O means there are 2 atoms of hydrogen and one of oxygen.
If there is more than one of whole groups of atoms, then that’s shown with a bracket around them. For example, calcium hydroxide has one calcium (Ca) for every two hydroxides (OH), so is written as Ca(OH)2.
If a charge is present, it’s indicated in superscript, with a sign (+/-) and a number if more than one charge is present. For example, calcium ions have two positive charges so are written Ca2+.
Sometimes a formula can be written in a way that gives an indication of the structure. A chemical equation shows a reaction taking place. On the left-hand side are the reactants, the molecules that take part in the reaction. On the right-hand side are the products, the molecules that are created in the reaction. Each side must contain the same number of each kind of atom. An arrow between them indicates the direction the reaction is expected to occur:
Ca + Cl2 → CaCl2
Calcium + chlorine → Calcium chloride
If there are two or more of any molecules, that’s indicated with a number in front of the molecule:
CH4 + 2O2 → CO2 + 2H2O
One methane molecule + two oxygen molecules → one carbon dioxide molecule and two water molecules
An equation may sometimes specify which phase each molecule is in – whether it’s solid, liquid, or gas, or if it’s dissolved. This is written in brackets after the molecule – (s) for solid, (l) for liquid, (g) for gas, and (aq) for ‘aqueous’, meaning dissolved in water. For example, solid calcium carbonate reacts with carbonic acid in water to form calcium bicarbonate, which is much more soluble so becomes dissolved in water:
CaCO3 (s) + H2CO3 (aq) → Ca(HCO3)2 (aq)
Solid calcium carbonate + dissolved carbonic acid → dissolved calcium bicarbonate
All chemical reactions can actually proceed in either direction. Most of the time, one direction is expected to take place more strongly, so the arrow is written in that direction. However, many common reactions happen in both directions simultaneously, creating an equilibrium where the reactions are taking place but there is no net change in concentration from one side to the other. This is indicated with the symbol ⇌.
For example, carbonic acid in water is continually breaking down into bicarbonate and hydrogen ions – but the ions are also continually joining back together.
H2CO3 ⇌ HCO3– + H+
Carbonic acid ⇌ bicarbonate + hydrogen ions
VA ROGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG
Answer:
Pppppppppppppppppppppppppppppp
What is a jet stream. in your own words but be more detailed about what you say.
(don't send a link or file)
For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?
OA 13
OB. 14
OC 26
OD. 27
O E 40
Answer:
14...................
Look at the chemical equation.
HI (aq) + LiOH (aq) → LiI (aq) + H2O (l)
a) What is the total ionic equation?
b) What is the net ionic equation?
c) What is/are the spectator ion(s)?
d) What is the salt that is formed?
Answer:
See explanation
Explanation:
a) The total ionic equation shows all the ions involved in the equation as follows;
H^+(aq) + I^-(aq) + Li^+(aq) + OH^-(aq) ----> Li^+(aq) + I^-(aq) + H2O(l)
b) The net ionic equation only involves the ions that truly participated in the reaction.
H^+(aq) + OH^-(aq) ----> H2O(l)
c) The spectator ions appear on both sides of the reaction equation. They are; I^- and Li^+.
d) The salt formed is LiI (lithium iodide)
What is the LD50 of a substance?
In toxicology, the median lethal dose, LD₅₀, LC₅₀ or LCt₅₀ is a measure of the lethal dose of a toxin, radiation, or pathogen. The value of LD₅₀ for a substance is the dose required to kill half the members of a tested population after a specified test duration.
How many grams are in 0.428 moles of lithium carbonate, Li3PO4?
42.7
49.6
54.8
72.3
How can I calculate pH given pOH of 4.5?
Answer:
To find the pOH, simply subtract the pH from 14. In order to calculate the pOH, take the negative log of the hydroxide ion concentration.
An 18.0 g sample of unidentified metal was heated from 21.5°C to 89.0°C.
292 J of heat energy was absorbed by the metal in the heating process.
Calculate the specific heat of the metal to determine its identity.(need work show, or how you got the answer)
A.calcium
B.iron
C.copper
D.silver
Answer: (d)-Silver
Explanation:
Given
The mass of sample is [tex]m=18\ gm[/tex]
It is heated from [tex]21.5^{\circ}C[/tex] to [tex]89^{\circ}C[/tex]
heat energy absorbed is [tex]292\ J[/tex]
Heat absorbed is given by [tex]Q=mc\Delta T[/tex]
Insert the values
[tex]\Rightarrow 292=18\times c\times [89-21.5]\\\Rightarrow 292=18\times c\times 67.5\\\\\Rightarrow c=\dfrac{292}{1215}\\\\\Rightarrow c=0.24\ J/g^{\circ}C[/tex]
As per the table, it is Silver
What is the chemical name for 1 nitrogen atom,
2 hydrogen atom?
NH3 has 1 Nitrogen atom and 3 hydrogen atoms.
How is ethanol DIFFERENT from gasoline?
A. Ethanol is alcohol; gasoline is fuel.
B. Ethanol becomes a bacteria; gasoline becomes a chemical.
C. Ethanol helps break down yeast; gasoline is a by-product of
yeast.
D. Ethanol is made from oranges; gasoline is made from
petroleum
how are living organisms in an ecosystem linked
Answer:
An environment is a local area of living creatures existing related to the nonliving segments of their current circumstance, interfacing as a framework. These biotic and abiotic segments are connected together through supplement cycles and energy streams.
Explanation:
Answer:
Living organisms require a proper, stable ecosystem/envirornment to function
Explanation:
The fungus known as “chicken of the woods” grows on trees. the fungus breaks down the tree and gets its nutrients that way. the tree decays gets weak and becomes very vulnerable to extreme weather.
Benefits, harmed, parasitism
Answer:
the answer is harmed
Explanation:
Brainliest plzzzzzzzzzz
Why is Dalton's Gas Law a problem for people who visit high altitudes?
The pressure of a 980.0 mL sample of gas at a constant temperature is increased from 0.4620 atm to
0.6320 atm. What is the final volume of the gas?
Answer:
P
1
V
1
T
1
=
P
2
V
2
T
2
Explanation:
P
1
V
1
T
1
=
P
2
V
2
T
2
, given a constant quantity of gas.
And thus,
P
1
×
V
1
×
T
2
V
2
×
T
1
=
P
2
, even given this format, we can see the problem is dimensionally sound. We do need to use
absolute temperature.
P
2
=
1.00
⋅
a
t
m
×
250
⋅
m
L
×
313
⋅
K
500
⋅
m
L
×
293
⋅
K
≅
1
2
⋅
a
t
m
.
Explanation:
a compound formed when atoms of two or more different elements share electrons
a compound formed when atoms of two or more different elements share electrons
This statement is true.
HURRY PLEASE
What volume is occupied by 3.12 moles of a gas when the pressure is 88.4 kPa at a temperature of 19℃?
Answer:
The Combined Gas Law shows that the pressure of a gas is inversely proportional to volume and directly proportional to temperature. Avogadro's Law shows that volume or pressure is directly proportional to the number of moles of gas. Putting these together leaves us with the following equation:
P1×V1T1×n1=P2×V2T2×n2(11.9.1)
As with the other gas laws, we can also say that (P×V)(T×n) is equal to a constant. The constant can be evaluated provided that the gas being described is considered to be ideal.
The Ideal Gas Law is a single equation which relates the pressure, volume, temperature, and number of moles of an ideal gas. If we substitute in the variable R for the constant, the equation becomes:
P×VT×n=R(11.9.2)
The Ideal Gas Law is conveniently rearranged to look this way, with the multiplication signs omitted:
PV=nRT(11.9.3)
The variable R in the equation is called the ideal gas constant.
Explanation:
4. Use the particle theory to explain density.
Answer:
Density is the total number of particles in a given volume
Explanation:
As per the particle theory, density is defined as total space occupied by certain number of particles of any given element with in a defined volume is termed as density.
Density is not the denseness of a single unit but the space occupied by many single units with in a given volume V
Hence, density is the total number of particles in a given volume.
Consider the following redox reaction:
2Cr(OH)3 + ClO3- + OH- CrO42- + 2 H2O
A) The reaction is balanced and occurred in an acidic environment
B) The reaction is unbalanced and occurred in a basic environment
C) The reaction is balanced and occurred in a basic environment
D) The reaction is unbalanced and occurred in an acidic environment
Answer:
kkahshsi
Explanation:
jsjysvs7xbzj sis zyhzoa w sizndkzjaos skzn8zjjzhxlx zjzjzjhzbsjz sksnzinsizjdi sis7gshsjsjsjiajwiwiw iajaja naskoh oe
an organism that lives in or on another organism and causes harm to is a
A. host
B. parasite
C. prey
D. producer
the answer is B. Parasite.
3. Balance the chemical equations
Answer:
A) BaCl2 + 2NaOH → Ba(OH)2 + 2NaCl
B) H2SO4 + 2KOH → K2SO4 + H2O
C) K2O3 + 2HCl → 2KCl + H2O + CO2
D) 2FeSO4 → Fe2O3 + SO2 + SO3
E) 2NaNO3 → 2 NaNO2 + O2
Explanation:
Answer:
A) BaCl² + 2NaOH → _Ba(OH)² + 2NaCl
B) H²SO⁴ + 2KOH → _K²SO⁴ + H²O
C) K²CO³ + 2HCl → _KCl + H²O + CO²
D) 2FeSO⁴ → _Fe²O³ + _SO² + _SO³
E) 2NaNO³ → 2NaNO² + _O²
What is the voltage of a galvanic cell made with zinc (Zn) and aluminum (AI)? A. 0.92 V
B. -0.92 V
c. -2.44 V
D. 2.44 V
Answer:
The correct option is (a) "0.92 V".
Explanation:
The voltage of a galvanic cell made with zinc (Zn) and aluminum (AI) is given by :
Voltage =Ered- Eoxd
Where
Ered = reduction potential
Eoxd = oxidation potential
As per reduction standard potentials, the emf of Zinc is -0.76 V and the emf of Aluminium is -1.66 V. So,
V = 0.76 - (-1.66)
= 0.9 V
Hence, the correct option is (a) "0.92 V".
When workers stop working entirely, it is called a(n)
Answer here
SUB
Answer:
Explanation:
When workers stop working entirely, it is called either a strike or retirement, depending on the circumstances under which it is done. A strike is a mass refusal of employees to work, because they are not satisfied.
Retirement on the other hand happens when the employee reaches certain age, after which he/she can leave the job and get a pension,.
What series of decays would allow you to turn Lead, Pb-207 into Gold, Au-199?
Answer:
Two alpha particle decays and one beta particle decay.
Explanation:
If Lead Pb-207 is to turn into Gold, Au-199, there needs to be a drop in mass number from 207 to 199. That drop is 207 - 199 = 8.
Since the mass number of an alpha particle(⁴₂He) is 4, to lose 8 nuclear particles(neutron + proton), we need 8 particles/nucleus ÷ 4 particles per alpha particle nucleus = 2 alpha particles.
The nuclear equation is given below
²⁰⁷₈₂Pb → ¹⁹⁹₇₉Au + ⁴₂He + ⁴₂He
Note that the charge is not balance
82 ≠ 79 + 2 + 2 = 83
For this to be balanced, we need to lose a beta particle, ⁰₋₁e. So, our equation becomes
²⁰⁷₈₂Pb → ¹⁹⁹₇₉Au + ⁴₂He + ⁴₂He + ⁰₋₁e
So, series of decays would allow you to turn Lead, Pb-207 into Gold, Au-199 are two alpha particle decays and one beta particle decay.
The shape of the methane molecule(ch4) is called
Answer:
Tetrahedral
Explanation:
Please help me I need help.
Ms. Kastenberg spilled a bottle of paint outside in the sun. Over time, the paint dried. This is because:
A
The paint reflected the energy from the light
B
The light was too strong for the paint
с
The sun removed energy from the paint
D
The paint absorbed the energy from the light
Answer:
I believe that the answer is the paint absorbed the energy from the light
Explanation:
The paint dried because the paint absorbed the energy from the light and the correct option is option D.
What is absorption of light?Light absorption is the process in which light is absorbed by matter and converted into energy. In an atom, electrons vibrate at a specific frequency – this is called the natural frequency.
If a wave of light hits a material in which the electrons are vibrating at the same frequency as the wave of light, the electrons will absorb the energy and convert it into vibrational motion.
This is why objects have different colours – different materials’ electrons will vibrate at different rates, and therefore absorb different frequencies of light.
Therefore, the paint dried because the paint absorbed the energy from the light and the correct option is option D.
Learn more about Absorption of light, here:
https://brainly.com/question/3080788
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1.0 moles of an ideal gas are held in a container under 2.0 atm of pressure and 310 K. What must be the volume of this container?
Answer:
12.7 L (3 s.f.)
Explanation:
Since it is an ideal gas, we can apply the ideal gas law:
[tex]\boxed{pV=nRT}[/tex]
☆ where p= pressure
V= volume
n= number of moles
R= ideal gas constant
T= temperature
Substitute all the given information into the formula:
2V= 1(0.08206)(310)
2V= 25.4386
V= 25.4386 ÷2
V= 12.7 L (3 s.f.)
Further explanation:
The ideal gas constant, R, has different values depending on what units are being used. Two examples are listed below:
[tex]• \: 0.08206 \: L \: atm ^{ - 1} \: mol \: K[/tex]
[tex]• \: 8.314 \: J \: {mol}^{ - 1} \: {K}^{ - 1} [/tex]
In the above question, we use the value 0.08206 because the pressure was given in atm and the temperature was given in Kelvin. Thus, the unit used for volume is L.
Answer: 12.7 L
Explanation:
P=2.0atm
V= ???
n=1.0 mol
R= 0.0821
T= 310K
PV=nRT--> (2)V=(1)(0.0821)(310)
V=12.7 L
if you can please give me the correct answer i’ll give you a brainliest only if it’s correct thanks!
Why is it important for the kitchen manager to make sure food is fresh?