Answer:
The top left number of the symbol of an atom is the sum of the protons and neutrons in the atom known as atomic mass number, while the bottom left number of the symbol of an atom is the number of protons in the atom known as atomic number.
Explanation:
An atom of an element is composed of other subatomic particles; the electron, proton and neutron. The number of protons present in an atom of an element is equal to the number of electrons present in the atom of that element and is known as the atomic number of the element. The number of neutrons present in the atom summed together with the proton number gives the atomic mass number of an atom of the element.
Elements are represented with symbols. In writing the symbols of elements, the atomic number and the atomic mass of an atom of the element is usually written along with the symbol. The top left number of the symbol of an atom is the sum of the protons and neutrons in the atom, while the bottom left number of the symbol of an atom is the number of protons in the atom.
For example, the element sodium has an atomic number of 11 and a mass number of 23. In symbols, it is written as follows: ²³₁₁Na
A gas has a pressure of 645 Torr at 128 ºC. What is the temperature (ºC) of the pressure increases to 824 Torr at constant volume and moles?
Answer:
512 K
Explanation:
Initial pressure P1 = 645 Torr
Initial Temperature T1 = 128 ºC + 273 = 401 K (Upon converting to kelvin temperature)
Final Pressure P2 = 824 Torr
Final Temperature T2 = ?
The relationship between the variables is given as;
P1 / T1 = P2 / T2
Making T2 subject if formula we have;
T2 = P2T1 / P1
Inserting the values we have;
T2 = 824 * 401 / 645 = 512 K
A sheet of aluminum measures 55.0 cm by 23.3 cm. If the volume is 2.90 cm^3 what is the thickness of the foil?
Express your answer with the appropriate units.
Answer:
0.0023 cm
Explanation:
The following data were obtained from the question:
Length (L) = 55 cm
Breadth (B) = 23.3 cm
Volume (V) = 2.9 cm³
Thickness (T) =?
Thus, we can obtain the thickness of the aluminum foil as illustrated below:
V = L × B × T
2.9 = 55 × 23.3 × T
2.9 = 1281.5 × T
Divide both side by 1281.5
T = 2.9/1281.5
T = 0.0023 cm
Therefore, the thickness of the aluminum foil is 0.0023 cm
A car's fuel efficiency is 39.0 miles per gallon. What is its fuel efficiency in kilometers per liter? (1.6094 km=1 mile)(1 gallon=3.79 L)
Answer:
the fuel efficiency in kilometers per liter is 16.561 kilometer per liter
Explanation:
The computation of the full efficiency in kilometers per liter is shown below:
39.0 miles ÷ gallon = (39.0 miles ÷ gallon) × (1.6094 km ÷ 1 miles) × (1 gallon ÷ 3.79 L)
Now cut the opposite miles and gallons
So, the fuel efficiency would be
= 16.561 kilometers per liter
Hence, the fuel efficiency in kilometers per liter is 16.561 kilometer per liter
how many atoms does sodium hypochlorite have?
Answer:
NaClO; the contained elements ae Na, Cl, O.
1. Name the structure that the arrow points to
Answer:
i have been doing research and i think its the style. if not its the pollen tube.
Explanation:
Hope i helped!
Answer:
stigma
Explanation:
2. Enumerate four Reactive Oxygen Species (ROS)
Answer:
Examples of ROS include peroxides, superoxide, hydroxyl radical, singlet oxygen, and alpha-oxygen.
Answer Question in box below Q: What is your evidence for why you think a Fan not spinning has energy or does not have energy-explain in detail?
Answer:
Yes, a fan not spinning has energy
Explanation:
Let us remember that energy is neither created nor destroyed but is transformed from one form to another. This is known as the principle of energy conservation. Hence energy in the universe never disappears!
The fan that is not spinning has potential energy. Potential energy is energy possessed by a body by virtue of its position. When the fan starts spinning, this potential energy is converted to kinetic energy.
A flask containing 100 g of water is heated, and the temperature of the water increases from 21°C to 90°C. How much heat did the water absorb if the
specific heat capacity of water is 4.184 J/gºC?
A. 289 J
B. 418.4 J
C. 28,870 J
D. 10,000 J
Answer:
28869.6J
Explanation:
Given parameters:
Mass of water in flask = 100g
Initial temperature = 21°C
Final temperature = 90°C
Specific heat capacity = 4.184J/g°C
Unknown:
Amount of heat the water absorbed = ?
Solution:
The amount f heat the water absorbed can be determined using the expression below:
H = m x C x Δt
m is the mass
C is the specific heat capacity of water
Δt is the change in temperature
Now insert the parameters and solve;
H = 100 x 4.184 x (90 - 21) = 28869.6J
Answer:
So its c
Explanation:
Convert 85km/hr to cm/s(factor label conversion)
Answer:
23.61m/s
Explanation:
Km/hr is a unit of expressing the speed of a body. Speed is the rate of change of distance with time. Also, the same unit is applicable for expressing the velocity of a body. But to find the velocity, we must emphasize the direction of motion of the body.
Given parameter:
85km/hr to cm/s
Note:
1000m =1km
3600s = 1hr
So;
85 x
Cancelling out km and hr;
= 85 x 0.278m/s
= 23.61m/s
Someone please help me!!!!
Double replacement :
2Na₃PO₄+3CaCl₂⇒6NaCl + Ca₃(PO₄)₂
Further explanation1. A single replacement reaction is a chemical reaction in which one element replaces the other elements of a compound to produce new elements and compounds
2. Double-Replacement reactions. Happens if there is an ion exchange between two ion compounds in the reactant to form two new ion compounds in the product
3. Combination/syntesis : 2 or more reactants combine to form a new compound
4. Decomposition : the reactant is decomposed into 2/more products
If we look at the reaction options available, all of them can be included in the double replacement reaction, but we only choose the reaction from Sodium phosphate and Calcium chloride which leads to options: C because it is balanced (from the number of atoms in the same reactant and product) and is in accordance with the chemical formula of each compound (both products and reactants)
A mixture of neon and xenon gases, at a total pressure of 739 mm Hg, contains 0.919 grams of neon and 19.1 grams of xenon. What is the partial pressure of each gas in the mixture?_______g Xe
Answer:
Partial pressure of neon = 175 mmHg
Partial pressure of xenon = 564 mmHg
Explanation:
The partial pressure of a gas in a mixture can be calculated as the product of the mole fraction of the gas (Xi) and the total pressure (Pt), as follows:
Pi = Xi Pt
The total pressure is 739 mmHg ⇒ Pt = 739 mmHg
In order to calculate the mole fraction of each gas, we have to first calculate the number of moles of each gas (n) by dividing the mass of the gas into the molar mass (MM):
For neon gas (Ne):
MM(Ne) = 20.18 g/mol
n(Ne)= mass/MM = 0.919 g x 1 mol/20.18 g = 0.045 mol Ne
For xenon gas (Xe):
MM(Xe) = 131.3 g/mol
n(Xe)= mass/MM = 19.1 g x 1 mol/131.3 g = 0.145 mol Xe
Now, we calculate the mole fraction (X) by dividing the number of moles of the gas into the total number of moles (nt):
nt= moles Ne + moles Xe = 0.045 mol + 0.145 mol = 0.190 mol
X(Ne) = moles Ne/nt = 0.045 mol/0.190 mol = 0.237
X(Xe) = moles Xe/nt = 0.145/0.190 mol = 0.763
Finally, we calculate the partial pressures of Ne and Xe as follows:
P(Ne) = X(Ne) x Pt = 0.237 x 739 mmHg = 175 mmHg
P(Xe) = X(Xe) x Pt = 0.763 x 739 mmHg = 564 mmHg
ammonia is______a base
Answer:
Ammonia is moderately a base
H20+ SO3 ? Which compound is likely produced by the chemical reaction?
Answer:
h2so4
Explanation:
im big brain.
5. What is metallic bonding?
6. Why are metals shiny?
Answer:
Metallic bonding is found in metals and their alloys. When the atoms give up their valence electrons, they form ions. These ions are held together by the electron cloud surrounding them. Metals are shiny because they have a lot of free (i.e. delocalized) electrons that form a cloud of highly mobile negatively charged electrons on and beneath the smooth metal surface in the ideal case. ... In the absence of any external EM field, the charges in the plasma are uniformly distributed within the metal.
Explanation:
In metallic bonding, the electrons are “surrendered” to a common pool and become shared by all the atoms in the solid metal.
The rms speed of the molecules of a gas at 145∘C is 187 m/s. Calculate the mass m of a single molecule in the gas.
The mass m of a single molecule in the gas is 32.19 g
The root square mean (R.M.S) velocity V of the molecules of a really perfect fuel is given with the aid of the expression, v=sqrt(3RTM) and v=sqrt(3KTm) where R is universal gas consistent, T is absolutely the (Kelvin) temperature, m is the molar mass, okay is Boltzmann's consistent and M is the molecular mass.
The basis-mean-square speed is utilized in fuel, for the measure of the speed of debris, mentioned as the square root of the common speed-squared of the molecules in a gas. it's far represented with the aid of the equation:
Calculation:-
vrms=√3RT/M,
M = √3RT/vrms
= 1.732 × (8.314) ×418 / 187
= 32.19 g
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A chemist prepares a solution of calcium sulfate (CaSO4) by measuring out 0.232 g of calcium sulfate into a 300.mL volumetric flask and filling the flask to the mark with water. Calculate the concentration in mol/L of the chemist's calcium sulfate solution. Be sure your answer has the correct number of significant digits.
Answer:
5.6667*10^-3mol\L
Explanation:
get the number of moles:
0.0232\(40+32+16+16+16+16)=1.7*10^-3
get the consentration:
1.7*10^-3 \0.3=5.6667*10^-3mol\L
An unknown metal has a mass of 77.3 g. When 3610 J of heat are added to the sample, the sample temperature changes by 52.1 ∘C. Calculate the specific heat of the unknown metal. Metal Specific heat (J/g⋅∘C) aluminum 0.897 tin 0.210 strontium 0.301 barium 0.204 calcium 0.650 nickel 0.440
Answer:
specific heat = .897 J /g°C
Explanation:
Quantity of heat added = mass x specific heat x rise in temperature
3610 = 77.3 x specific heat x 52.1
specific heat = .897 J /g°C
Unknown metal is Aluminium .
What does this passage explain about people?
why mothers favor some children over others
the contrasting sides of human nature
why there is harmony in all things
left- and right-handedness
Answer:
the contrasting sides of human nature
Explanation:
I took the test
What molecules are needed to make atp
Answer:
APT is made of a nitrogen base (adenine), a ribose sugar, and three phosphate groups.
Hope this helped! :)
Answer:
The energy released from each molecule of glucose is used to attach a phosphate to each of four molecules of adenosine diphosphate (ADP) to produce two molecules of adenosine triphosphate (ATP) and an additional molecule of NADH.
Explanation:
Identify the term that matches each electrochemistry definition.
a. An electrochemical cell powered by a spontaneous redox reaction.
b. The electrode where reduction occurs.
c. The electrode where oxidation occurs
d. An electrochemical cell that takes in energy to carry out a nonspontaneous redox reaction.
e. A chemical equation showing either oxidation or reduction.
1. Cathode
2. Anode
3. Galvanic cell
4. Half reaction
5. Electrolytic cell
The correct matches are:
a. 3. Galvanic cell.
b. 1. Cathode.
c. 2. Anode.
d. 5. Electrolytic cell.
e. 4. Half reaction.
What is electrochemistry?Electrochemistry is the study of chemical reactions in which movement of electron happen.
An electrolytic cell is the cell in oxidation and reduction occurs.
It's all about how electrical energy interacts with chemical transformation.
For example, is concerned with the study of electrochemical cells. It is concerned with cells that convert chemical to electrical energy.
Thus, the correct matches are a. 3. Galvanic cell.
b. 1. Cathode.
c. 2. Anode.
d. 5. Electrolytic cell.
e. 4. Half reaction.
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What would be the mass, in grams, of 1.505 x 1023 molecules of carbon disulfide?
Answer:
19g
Explanation:
Given:
Number of molecules = 1.505 x 10²³molecules
Formula of compound = CS₂
Unknown:
Mass of the compound
Solution:
A mole of every substance contains 6.02 x 10²³molecules. Using this we can find the number of moles from number of molecules given;
6.02 x 10²³molecules makes up 1 mole of a substance
1.505 x 10²³molecules will contain [tex]\frac{1.505 x 10^{23} }{6.02 x 10^{23} }[/tex] = 0.25mole of CS₂
Mass of CS₂ = number of moles x molar mass
Molar mass of CS₂ = 12 + 2(32) = 76g/mol
Mass of CS₂ = 0.25 x 76 = 19g
name the element whose atomicity is triatomic
Answer:
OZONE...............
5. To keep your lunch cold at the beach, would you want a material
that minimizes heat transfer or maximizes heat transfer? Explain (keep it short please)
Answer:
Minimizes heat transfer
Explanation:
To keep my lunch from getting cold at the beach, a material the minimizes heat transfer will be the most desirable.
Such material should be modified to prevent had transfer by convection, conduction and radiation. This kind of material is desirable because heat generally flows from a place of high amount to that of low amount. Since the food will mostly have a temperature higher than the ambient one, it is expected that heat will flow away from the food to the environment. This will make the food cold. If such heat transfer is prevented, then, the food will remain hot.In the reaction of silver nitrate with copper metal, metallic silver comes out of solution, and the solution turns blue. This as a ________ reactio
Answer:
Single displacement reaction.
Explanation:
Hello!!
In this case, since the reaction between silver nitrate and copper metal is:
[tex]2AgNO_3(aq)+Cu(s)\rightarrow 2Ag(s)+Cu(NO_3)_2(aq)[/tex]
As silver was forming silver nitrate, due to the presence of copper, which has the capacity to displace silver out of the salt, we notice the formation of solid silver and a resulting copper (II) nitrate which is blue in aqueous solution.
Therefore, this is a single displacement reaction, because the the lonely copper displaced the silver.
Best regards!
How many milliliters of 6.2 M M HCl H C l solution are needed to obtain 0.18 mol m o l of HCl H C l ?
Answer:
29 mL HCl
General Formulas and Concepts:
Chem
Molarity = moles of solute / liters of solutionExplanation:
Step 1: Define
6.2 M HCl
0.18 mol HCl
x L mol HCl
Step 2: Define conversions
1 L = 1000 mL
Step 3: Find L
6.2 M HCl = 0.18 mol HCl / x L HCl
(x L HCl)(6.2 M HCl) = 0.18 mol HCl
x L HCl = 0.18 mol HCl / 6.2 M HCl
x = 0.029032 L HCl
Step 4: Convert
[tex]0.029032 \ L \ HCl(\frac{1000 \ mL \ HCl}{1 \ L \ HCl} )[/tex] = 29.0323 mL HCl
Step 5: Check
We are given 2 sig figs. Follow sig fig rules.
29.0323 mL HCl ≈ 29 mL HCl
Answer:
29 mL HCl
Explanation:
Which diagram shows what can happen when a small force affects the lithosphere without causing a break?
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What volume will be occupied by 33.0 grams of CO2 at 500 torr and 27 °C?
Answer:
V = 27.98 L
Explanation:
Given data:
Mass of CO₂ = 33.0 g
Pressure = 500 torr
Temperature = 27°C
Volume occupied = ?
Solution:
Number of moles of CO₂:
Number of moles = mass/molar mass
Number of moles = 33.0 g/ 44 g/mol
Number of moles = 0.75 mol
Volume of CO₂:
PV = nRT
R = general gas constant = 0.0821 atm.L/ mol.K
Now we will convert the temperature.
27+273 = 300 K
Pressure = 500 /760 = 0.66 atm
By putting values,
0.66 atm×V = 0.75 mol × 0.0821 atm.L/ mol.K × 300 K
V = 18.47 atm.L/0.66 atm
V = 27.98 L
The volume that will be occupied by 33.0 grams of CO2 at 500 torr and 27 °C is 28.11L.
IDEAL GAS LAW:The volume of an ideal gas can be calculated using the ideal gas law equation as follows:
PV = nRT
Where;
P = pressure (atm)V = volume (L)n = number of moles (mol)R = gas law constant (0.0821 Latm/molK)T = temperature (K)According to this question;
P = 500torr = 0.657atmV = ?n = 33/44 = 0.75molT = 27°C = 27 + 273 = 300K0.657 × V = 0.75 × 0.0821 × 300
0.657V = 18.4725
V = 18.4725 ÷ 0.657
V = 28.11L
Therefore, the volume that will be occupied by 33.0 grams of CO2 at 500 torr and 27 °C is 28.11L.
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How is zinc chloride formed
Answer:
Explanation:
Zinc chloride, ZnCl2, can be prepared by a direct reaction or by evaporating the aqueous solution formed in various reactions. It is strongly deliquescent (water-absorbing) and is utilized as a drying agent and as a flux.4
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sulfur trioxide is used in many products from explosive to glue. which two criteria are most important in engineering a process to produce this compound?
Answer: The process should produce a high volume of product from the input reactants. The process must also be safe for people and the enviorment. - Ape x
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. Therefore, the process must also be safe for people and the environment.
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.
An ionic compound is a metal and nonmetal combined compound. Ionic compound are very hard. They have high melting and boiling point because of strong ion bond.
The process should produce a high volume of product from the input reactants. The process must also be safe for people and the environment.
Therefore, the process must also be safe for people and the environment.
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what causes convection currents in a gas or liquid?
Answer:
Convection currents are caused by a temperature difference in gases and liquids. As one area becomes warmer than another the molecules have more energy and start vibrating more vigorously thus spreading out and becoming less dense. This means that the less dense parts will become more buoyant causing them to rise.
Explanation:
Answer:
Convection currents are caused by a temperature difference in gases and liquids.
Explanation:
As one area becomes warmer than another the molecules have more energy and start vibrating more vigorously thus spreading out and becoming less dense. This means that the less dense parts will become more buoyant causing them to rise.