Answer:
The same number of each type of atom will always be present before and after a chemical reaction takes place.
Explanation:
pls mark as brainliest
What is the molecular formula for a compound that is 44.87% potassium, 36.7%
oxygen, 18.0% sulfur and a molecular mass of 696g.
Answer:
Molecular formula: S4K8O16 empirical formula: SK2O4
Explanation:
First we find the moles of each by first finding grams (using the percent) and then using stoichiometry to convert into moles:
Sulfur: 696 *.18 = 125.28grams S* [tex]\frac{1 mole S}{32.065 g S} = 3.907 moles S[/tex]
Potassium: 696 *.4487 = 312.2952 *[tex]\frac{1 mole K}{39.08 g K}[/tex]= 7.99117 mole K
Oxygen: 696 * .367 = 255.432 * [tex]\frac{1 mol O}{16g O}[/tex] = 15.9654 mole O
Then we divide each value by the atom with the smallest number of moles to find the mole ratio:
3.907/3.907= 1
7.99117 mole K/ 3.907= 2.043
15.9654 mole O/ 3.907= 4.08
The empirical formula is SK2O4
To find the molecular formula, we divide the mass given (696) by the mass of the empirical formula (174.22) to get 4. We then divide each atom by 4.
Molecular formula: S4K8O16
WILL GIVE 10 PTS AND BRAINIEST FOR THE RIGHT ANSWER PLEASE HELP!!!
____ is important for making amino acids, proteins, and the chlorophyll a plant uses to carry out photosynthesis.
A. Boron
B. Nitrogen
C. Potassium
D. Phosphorus
E. Calcium
Answer:
c
Explanation:
How many moles are there in 7.24 grams of calcium carbonate? With work shown
Answer:
0.0723371390261859
(feso4.(Nh4) So4. 6H2o) +Kmno4+H2So4_Fe2(So4)3+K2So4+mnSo4+(Nh4)2So4+H2o
Answer:
balancing the equation?
Which statement correctly describes the conductivity of the specified material?
Gold has a high conductivity
Most plastics have a high conductivity
Most wires are made to have a low conductivity
Copper has a low conductivity
Answer:
Gold has a high conductivity
Explanation:
This is because gold is a metal that occur free in nature in rocks, alluvial , grains e.t.c. it is a transition metal and in group 11 of the periodic table do it conduct electricity. It has has conductivity because it is a metals because all metals have ability to conduct electricity. When it is pure, it is a bright, slightly reddish yellow, . It is soft, malleable.
It is a ductile metal
and ductile metal.
Answer:GOLDDDDD
Explanation:
Which unit is used for measuring atomic mass?
А.atomic mole
B. grams/mole
C. grams
D. atomic mass unit
E. atomic mass weight
All of the following are physical changes except
A. ice melting.
B. plaster hardening.
C. paint drying.
D. rocket fuel burning.
Answer:
rocket fuel burning i think
Observe: Select the Show polar molecule inset checkbox. The animation shows the probable location of electrons (orange dots) in a polar molecule. A. What do you notice about the distribution of the electrons? B. How does this electron distribution affect the charges of the bonded atoms?
Answer:
A. In a polar molecule, the bond is polar covalent. That is, the electrons are shared but are slightly more attracted to the more electronegative atom. That part of the molecule has a negative partial charge density, and the other has a positive partial charge density (there is no symmetry in the distribution of the electricity density)
B. Charges are not affected, the molecule is neutral because electrons are shared. A molecule has the same number of electrons and protons which balance the charges in a molecule. Since all atoms are electrically neutral, then when they combine the form of a neutral molecule.
Explanation:
To determine polarity, the geometry of the molecule must be taken into account to determine the distribution of atoms and their electronegativity (tendency to attract electrons) to determine to which points of the molecule the electrons will be most attracted.
Atoms can share electrons to form chemical bonds and thus form different compounds. In the case of non-polar molecules, when formed in a covalent bond (two atoms bond by sharing valence electrons reaching "stable octet") between equal atoms, the molecule is neutral since it has zero electric charge. In this type of bond there is no change in the oxidation number of the atoms because their shared electrons are equidistant. Covalent bonds in which the electrons are shared equally are called non-polar covalent bonds. This is because the atoms are just the same, they have the same electronegativity, so they "attract" the electrons with the same force and the electrons surround the atoms equally. The charge density distribution is the same for both, there is asymmetry in the distribution of it.
Polar molecules are formed when bonds are formed by different atoms with large differences in electronegativity. The molecule is electrically neutral as a whole because it has an equal number of positive and negative particles, but there is no symmetry in the distribution of the electricity density. A polar bond is one in which a pair of electrons is more attracted to one of the atoms. This causes one end of the molecule to acquire a positive partial charge density and the other end of the molecule to acquire a positive partial charge density and the other end of the molecule to acquire a negative partial charge.
So, as a summary:
A. In a polar molecule, the bond is polar covalent. That is, the electrons are shared but are slightly more attracted to the more electronegative atom. That part of the molecule has a negative partial charge density, and the other has a positive partial charge density (there is no symmetry in the distribution of the electricity density)
B. Charges are not affected, the molecule is neutral because electrons are shared. A molecule has the same number of electrons and protons which balance the charges in a molecule. Since all atoms are electrically neutral, then when they combine the form of a neutral molecule. Only ions do not have a neutral electrical charge because of the process of gaining or losing electrons. An ion with a positive electrical charge is called a cation, and an ion with a negative electrical charge is called an anion.
You are given a sample of several compounds to separate by paper chromatography. You draw a pencil line exactly 1.00 cm from the bottom of the paper, and place a spot of sample on it. You dry the sample, then develop it in a solvent. When the chromatogram is taken out of the solvent, the paper is wet up to 9.2 cm from the bottom of the sheet. The compound you are interested in shows up as a spot 7.1 cm from the bottom of the paper. Calculate the following:
a. How far did the compound move?
b. In the same time, how far did the solvent move?
c. What is the Rf factor for the compound?
Answer:
a) 6.3 cm
b) 8.0 cm
c) 0.7875
Explanation:
(a) The compound has moved above upto 7.3 cm from the bottom of the paper. Let us assume that line is drawn at 1.0 cm mark as the origin of spot. \
Distance traversed by compound= 7.3 - 1.0 cm = 6.3 cm
(b) Distance traversed by the solvent = 9.0 - 1.0 cm = 8.0 cm
(c) The Rf = Compound Migration distance / Solvent front migration distance
= 6.3/8.0 = 0.7875
A 1,900-m3 water tower has been cleaned with a chlorine solution. The vapors of chlorine in the tower exceed allowable concentrations for the work crew to enter and finish repairs. If the chlorine concentration is 15 mg/m3 and the allowable concentration is 0.0015 mg/L, how long must the workers vent the tank with clean air flowing at 2.35 m3/s
Answer:
t = 1862 s
Explanation:
To do this, we need first to determine the theorical detention time, which can be determined with the following expression:
t₀ = ∀/Q (1)
Where:
t₀: detention time
∀: Volume of the fluid in the reactor
Q: Flow rate in the reactor
With this time, we must use the following expression to determine the time that the workers will take to vent the tank:
C = C₀ e^(-t/t₀) (2)
From here, we must solve for time t, and the expression will be:
t = ln(C₀/C) * t₀ (3)
Now that we know the expression to use, let's solve for t. Using (1) to determine the detention time, ∀ is 1900 m³, and Q is 2.35 m³/s so:
t₀ = 1900 / 2.35 = 808.51 s
Now, let's solve for the time t. C will be 0.0015 mg/L (or 1.5 mg/m³ cause in 1 m³ we have 1000 L) and C₀ 15 mg/m³:
t = ln(15/1.5) * 808.51
t = 1861.66 s or simply 1862 sHope this helps
The eye can see colors because:
a. the cones in the retina send signals to the brain.
b. the rods in the cornea send signals to the brain.
c. the optic nerve determines the color of the object and sends signals to the brain
d. None of the choices are correct.
Answer:
The answer is A, I think.
Answer:
the answer is A
Explanation:
The human eye and brain together translate light into color. Light receptors within the eye transmit messages to the brain, which produces the familiar sensations of color. Newton observed that color is not inherent in objects. Rather, the surface of an object reflects some colors and absorbs all the others.
What type of changes would you expect as you go down from the ocean's surface to
its bottom?
1.Temperature, pressure, light, and density all decrease
2.Temperature and pressure increase; light and density decrease
3.Temperature and light decrease; pressure and density increase
4.Temperature and density decrease; light and pressure increase
Answer:
answer is the 4th one
Explanation:
The type of changes one might expect as one goes down from the ocean's surface to its bottom is that temperature and light decrease; pressure and density increase.
What is pressure?Pressure is defined as the force applied on an object perpendicular to it's surface per unit area over which it is distributed.Gauge pressure is a pressure which is related with the ambient pressure.
There are various units by which pressure is expressed most of which are derived units which are obtained from unit of force divided by unit of area . The SI unit of pressure is pascal .
It is a scalar quantity which is related to the vector area element with a normal force acting on it.It is distributed over solid boundaries and across arbitary sections of fluid normal to the boundaries at every point.
Learn more about pressure,here:
https://brainly.com/question/18431008
#SPJ2
As illustrated, the below manometer consists of a gas vessel and an open-ended U-tube containing a nonvolatile liquid with a density of 0.993 g/mL. The difference in heights of the liquid in the two sides of the manometer is 32.3mm when the atmospheric pressure is 765 mm Hg. Given that the density of mercury is 13.6 g/mL, the pressure of the enclosed gas is ________ atm. Group of answer choices
Answer:
1.01atm is the pressure of the gas
Explanation:
The difference in heights in the two sides is because of the difference in pressure of the enclosed gas and the atmospheric pressure. This difference is in mm of the nonvolatile liquid. The difference in mm Hg is:
32.3mm * (0.993g/mL / 13.6g/mL) = 2.36mmHg
As atmospheric pressure is 765mm Hg and assuming the gas has more pressure than the atmospheric pressure (There is no illustration), the pressure of the gas is:
765mm Hg + 2.36mm Hg = 767.36 mmHg
In atm:
767.36 mmHg * (1atm / 760 mmHg) =
1.01atm is the pressure of the gas
Given:
Density of mercury = 13.6 g/mLDensity of nonvolatile liquid = 0.993 g/mLDifference in height = 32.3mmAtmospheric pressure = 765 mm HgNow,
The density of Hg will be:
= [tex]\frac{13.6}{0.791}[/tex]
= [tex]17.2 \ mm[/tex]
then,
= [tex]32.3\times (\frac{1 \ mm \ Hg}{17.2} )[/tex]
= [tex]18.73 \ mm \ Hg[/tex]
hence,
The pressure will be:
= [tex]765-18.73[/tex]
= [tex]746.27 \ mm \ Hg[/tex]
= [tex]0.993 \ atm[/tex]
Thus the above answer is right.
Learn more about gas vessel here:
https://brainly.com/question/7205294
How many significant figures
are in this number?
5.67 x 10^2
Answer:
3
Step-by-step explanation:
Hence, the given number has 3 significant figures.
structure of 2,6-diiodo-4-methyl-5-propylheptane
Explanation:
2,6-Dibromo-4-isopropylphenol
2432-16-8
2,6-dibromo-4-propan-2-ylphenol
Phenol, 2,6-dibromo-4-(1-methylethyl)-
4-isopropyl-2,6-dibromophenol
Coach Scott hits a baseball with his bat to help his players with fielding
practice. The bat exerts a force on the ball, and the ball exerts an equal
and opposite force back on the bat.
A. Newton’s first law
B. Newton’s second law
C. Newton’s third law
Answer:
The ball exerts an equal and opposite force on the bat. This is the reaction force. Such an interaction pair is another example of Newton's Third Law. The baseball forces the bat in one direction and the bat forces the ball in the opposite direction.
Identify the acid,
Base and salt of following.
b) lime water
d) potassium oxide
coppor sulphate
( vinegar
Answer:
Lime water Ca(OH)2 is a base
Potassium oxide K2O is a basic oxide
Copper sulphate CuSO4 is a salt
And vinegar is an acid
Explanation:
A 51.1g sample of brass is put into a calorimeter (see sketch at right) that contains 250.0g of water. The brass sample starts off at 95.4°C and the temperature of the water starts off at 25.0°C. When the temperature of the water stops changing it's 26.4°C. The pressure remains constant at 1atm.
Required:
Calculate the specific heat capacity of brass according to this experiment.
Answer:
0.415 j/g°C
Explanation:
Given that :
Mass of water, m1= 250.0 g
Temperature of water, T1= 25°C
Specific heat capacity of water, C= 4.184 J/g°C
Mass of brass , m2= 51.1g
Temperature of brass = 95.4°C
Specific heat capacity of brass , c2=?
Final temperature = 26.4°C
Heat lost by brass = Heat gained by water
mc(dT) = mc(dT)
51.1 * c * (95.4 - 26.4) = 250 * 4.184 * (26.4 - 25)
51.1 * 69 * c = 250 * 4.184 * 1.4
3525.9c = 1464.4
c = 1464.4 / 3525.9
c = 0.4153265
c = 0.415 j/g°C
Specific heat capacity of Brass for the experiment = 0.415 j/g°C
importance of distillation column in industry
Answer:
Distillation columns are used to separate mixed feed streams into their own distinct products.
Explanation:
The primary function of the distillation column is to separate the feed stream into (at least) one highest level product stream and one bottom product stream. The performance of the column separation can be justified by the purity of the upper and lower product streams.
GIVING BRAINLIEST AND 20 POINTS
Which number represents precipitation on the hydrologic cycle diagram?
1
2
3
4
Answer:
Number three, because precipitation is rain, which comes from cumulonimbus clouds. Precipitation happens when clouds have accumulated enough evaporated water for the cloud to get heavy and need to get rid of some of the water, which it does through condensing the water and then delivering it as rain.
Hope this helps! Have a wonderful day! (Please give me brainliest and thank you!)
:)
A student dissolves 10.2 g of sodium hydroxide (NaOH) in 250. g of water in a well-insulated open cup. He then observes the temperature of the water rise from 21.0 °C to 32.7 °C over the course of 3.7 minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction: NAOH(s) → Na" (aq) + OH (aq) You can make any reasonable assumptions about the physical properties of the solution. Be sure answers you calculate using measured data are rounded to 3 significant digits. do Note for advanced students: Its possible the student did not do the experiment carefully, and the values you calculate may not be the same as the known and published values for this reaction. O exothermic Is this reaction exothermic, endothermic, or neither? O endothermic O neither If you said the reaction was exothermic or endothermic, calculate the amount of heat that was released or absorbed by the reaction in this case. kJ Calculate the reaction enthalpy AH per mole of NaOH. mol
Answer:
A) The reaction is an exothermic reaction
B) 12.744 kJ
c) 49.976 KJ/mol . NaOH
Explanation:
A) The reaction is an exothermic reaction
B) calculate the amount of heat that was released or absorbed by the reaction in this case. kJ
Assuming : specific heat of solution = specific heat of water = 4.186 J/g°C
mass of solution = 10.2 + 250 = 260.2 g
determine The heat released in the reaction
= mass of solution * specific heat of solution * temperature change
= 260.2 * 4.186 * ( 32.7 - 21 )
= 12.744 kJ
C) Calculate the reaction enthalpy ΔH per mole of NaOH. mol
Reaction enthalpy = - heat released / ( 10.2 /40 )
= - 12.744 / ( 10.2/40 ) = - 49.976 KJ/mol . NaOH
A gas occupies 135 cm3 at 143. K. At what Celsius temperature will its volume be 140 cm3? Assume that pressure remains constant.
Answer:
New temperature T2 = -124.7 °C
Explanation:
Given:
Old volume V1 = 135 cm³
New volume V2 = 140 cm³3
Old temperature T1 = 143 K
Find:
New temperature T2
Computation:
V1 / T1 = V2 / T2
135 / 143 = 140 / T2
New temperature T2 = 148.3 K
New temperature T2 = 148.3 - 273
New temperature T2 = -124.7 °C
Pleaseee I need help and it is urgent
Answer:
1)4180j
2)15000kj
Explanation:
[tex]1) E=100*(30-20)*4.18=4180j\\2)Q=.5*30*1000=15000kj[/tex]
According to the combined gas law, pressure is inversely proportional to volume and directly proportional to temperature, and volume is directly proportional to temperature.
True
B. False
Save & Cont
How does a temperature increase cause the rate of a reaction to increase?
A. It increases the kinetic energy of the molecules.
B. It decreases orientation requirements of the molecules.
C. It increases the equilibrium constant for the reaction.
D. It decreases the activation energy of the reaction.
Answer:
B
Explanation:
"The temperature increases cause the rate of a reaction to increases the kinetic energy"
What is rate of reaction?
The reaction rate, also known as the rate of reaction, is the rate for which a chemical reaction occurs, and is proportional to increase in product concentration per unit time and the reduction in reactant concentration per unit time. The rate of reaction varies greatly.
What is kinetic energy?
An object's kinetic energy is the energy it has as a result of its motion. It is the amount of work required to push a body of a given mass from rest to a certain velocity. The body keeps its kinetic energy gained during acceleration unless that speed changes.
To know more about rate of reaction click here.
https://brainly.com/question/3334857.
#SPJ2
1. 1 N2+ 3 H2→2 NH3
c.How many moles of nitrogen are needed to produce 12 moles of nitrogen trihydride?
[tex]\displaystyle 6 \ mol \ N_2[/tex]
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to RightChemistry
Atomic Structure
Writing CompoundsStoichiometry
Using Dimensional AnalysisReactions RxNExplanation:Step 1: Define
[RxN - Balanced] N₂ + 3H₂ → 2NH₃
[Given] 12 mol NH₃
[Solve] x mol N₂
Step 2: Identify Conversions
[RxN] 1 mol N₂ → 2 mol NH₃
Step 3: Stoich
[DA] Set up: [tex]\displaystyle 12 \ mol \ NH_3(\frac{1 \ mol \ N_2}{2 \ mol \ NH_3})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 6 \ mol \ N_2[/tex]Answer:
[tex]\boxed {\boxed {\sf 6 \ moles \ of \ N_2}}[/tex]
Explanation:
1. Balance Equation
We are given the reaction:
[tex]1 N_2+3H_2 \rightarrow 2 NH_3[/tex]
The equation is already balanced. Both sides have 2 moles of nitrogen and 6 moles of hydrogen.
2. Conversions
In this reaction, 1 mole of nitrogen produces 2 moles of nitrogen tryhdride:
[tex]1 \ mol \ N_2 \rightarrow 2 \ mol \ NH_3[/tex]
3. Stoichiometry Calculations
Use the conversion rate as a fraction.
[tex]\frac{ 1 \ mol \ N_2}{2 \ mol \ NH_3}[/tex]
Multiply the number of moles of nitrogen trihydride produced: 12 moles.
[tex]12 \ mol \ NH_3 *\frac{ 1 \ mol \ N_2}{2 \ mol \ NH_3}[/tex]
The moles of nitrogen trihydride cancel.
[tex]12 *\frac{ 1 \ mol \ N_2}{2} = \frac{ 12 \ mol \ N_2}{2}[/tex]
[tex]6 \ mol \ N_2[/tex]
6 moles of nitrogen are needed to produce 12 moles of nitrogen trihydride.
how to rapidly separate red#40 from ZnO
Answer:
your question :how to rapidly separate red#40 from ZnO
answer :Red #40 is soluble in water while zinc oxide is not. 4- heat the solution of red #40 and water until water evaporates and red#40 remains
hope it's help
#carryONlearningIn the following reduction of iron ore, 3C + 2Fe2O3 –> 4Fe + 3C02, iron is reduced and _____ is oxidized.
A) carbon dioxide
B) carbon
C) iron oxide
D) oxygen
Answer:
B carbon
Explanation:
guessed
4 moles of monoatomic ideal gas is compressed adiabatically causing the temperature to increase from 300 K to 400 K. Calculate the work done on the gas in units of Joules (if the answer is negative, be sure to enter a negative sign in your answer).
Answer:
the work done on the gas is 4,988.7 J.
Explanation:
Given;
number of moles of the monoatomic gas, n = 4 moles
initial temperature of the gas, T₁ = 300 K
final temperature of the gas, T₂ = 400 K
The work done on the gas is calculated as;
[tex]W = \Delta U = nC_v(T_2 -T_1)[/tex]
For monoatomic ideal gas: [tex]C_v = \frac{3}{2} R[/tex]
[tex]W = \frac{3}{2} R \times n(T_2-T_1)[/tex]
Where;
R is ideal gas constant = 8.3145 J/K.mol
[tex]W = \frac{3}{2} R \times n(T_2-T_1) \\\\W = \frac{3}{2} (8.3145) \times 4(400-300) \\\\W = \frac{3}{2} (8.3145) \times 4(100)\\\\W = 4,988.7 \ J[/tex]
Therefore, the work done on the gas is 4,988.7 J.
PLEASE HELP
MY PARENTS WILL KILL ME IF I DONT GET MY SCHOOL WORK DONE BY 12 PM TODAY!! AND I DONT UNDERSTAND IT!!
If the mass of an unknown object is 2 grams and the volume is 2.35 cubic centimeters, what is the density of that object?
a. _________________________
b. Look back at Table 4.1. Based on your calculated density, what is the substance? _________________________
Answer:
oh ok
Explanation: