Answer:
121 aprox.
Explanation:
mass/molar mass = Q/CF
where mass=?
molar mass of Al=27
Q=It = 15×24×60×60
C=3
F=96500
1. What is the volume of 4.00g of aluminum at STP?
Answer:
22.4cm³
Explanation:
Avogadro's law shows that Avogadro's volume is 22.4
In explosive combustion the rapid expansion of --------------- causes explosion and the production of ------------------
Answer:
Volume; high temperature and pressure
Explanation:
In an explosive combustion the rapid expansion of the volume causes explosion and the production of high temperature and pressure.
The substance is usually in a confined place and the expansion usually reaches a breaking point in which it is expelled from the space usually accompanied with a loud noise and high amount of temperature and pressure change thereby releasing its gas constituents.
HELP ;-;
Vanillin, C8H8O3, the principal component of vanilla beans, is very similar to glucose, C6H12O6 a type of sugar. Brittany Spears has a life threatening allergy to vanillin. After one of her concerts she was found dead in her dressing room. A glass lined with a white powder was found smashed on the floor next to her. Police think the glass was lined with vanillin suggesting she was murdered. A 2.54 g sample of this powder underwent carbon-hydrogen analysis. It’s combustion was found to produce 5.875 g of CO2 (g) and 2.41 g of H2O(g) . Find the empirical formula of this compound and determine if Brittany may have been poisoned?
b) Is this evidence enough to conclude for certain that the identity of the powder on the glass is indeed vanillin? Why or why not?
Answer:
The empirical formula is: CH2
Th powder is not vainillin
Explanation:
We can find empirical formula of a compound CₐHₓOₙ knowing that moles CO2 = Moles C, 2 Moles H2O = Moles H and that we can find the mass of oxygen by the difference of masses of the atoms:
Moles C = Moles CO2 -Molar mass: 44.01g/mol-
5.875g * (1mol/44.01g) = 0.1335 moles C * (12.01g/mol) = 1.60gC
Moles H2O and moles H -Molar mass: 18.01g/mol-
2.41g H2O * (1mol / 18.01g) = 0.1339 moles H2O * (2mol H / 1mol H2O) =
0.2676 moles H * (1g/mol) = 0.27g H
The empirical formula of this compound is the ratio of C:H:
0.2676 moles H / 0.1335 moles C = 2
The empirical formula is:
CH2
In vainillin, the moles of Carbon = Moles of Hydrogen. the experiment shows the moles of hydrogen are twice the moles of carbon. Thus, the powder is not vainillin
Using the periodic table, choose the more reactive nonmetal.
Br or As
Reactivity of non-metals depend on their ability to gain electrons. So, smaller is the size of a non-metal more readily it will attract electrons because then nucleus will be more closer to valence shell. ... Hence, Br is the non-metal which will be more reactive than At.
Answer:
br is more reactive than as
Question 12 of 15
Matter can undergo chemical reactions and nuclear reactions. Which
statement is true for both types of reactions?
A. The reactants are changed to form the products.
B. The reactants can be elements or compounds.
C. The products can be elements or compounds.
D. The products can be the same as the reactants.
Answer:
A. The reactants are changed to form the products.
Explanation:
Chemical reactions are reactions that involves a change in the chemical composition of substances involved while a nuclear reaction is the process of fusing together or splitting the nucleus of an atom. According to this question, matter is said to undergo both types of reaction.
However, one similarity in both chemical and nuclear reactions is that substances called REACTANTS are changed to form PRODUCTS. In nuclear reaction, the atoms joined or split are the reactants while the ones formed are the products.
Answer: A
Explanation:
Which type of bond is found in an alkane?
O A. Double only
B. Single and double
O C. Single only
O D. Single and triple
Considering the definition of alkanes, single bonds are found in an alkane.
Definition of AlkanesAlkanes are a class of hydrocarbons (compounds containing only carbon and hydrogen) that are made up of a variable number of carbon atoms joined together by single bonds. In turn, each carbon atom bonds to hydrogen atoms, which may eventually be replaced by other atoms or functional groups.
In other words, alkanes are open or closed chain molecules that are linked by simple bonds.
Alkanes are saturated hydrocarbons because the bonds between carbon atoms are simple and stable. And as mentioned, the hydrogen atoms bonded to each carbon atom can be replaced by other atoms, such as halogens (fluorine, bromine, chlorine) or various groups or “radicals”. In the latter case, the structure becomes more complex giving rise to branched alkanes.
SummaryIn summary, single bonds are found in an alkane.
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Answer: C) single only
Explanation:
just got it right
The ideal gas law equation is: PV = nRT
Use the ideal gas law to calculate the moles of gas in a container that has a pressure
of 700kpa, volume of 2L and a temperature of 450K.
Answer:
The answer is the first option 0.37 moles
Explanation:
the ideal gas law is PV = nRT, so in the terms of n,
n = PV/RT (divide both sides by RT to let n stand alone)
given: P = 700 kpa, V = 2L, T = 450 K , R = 8.31
n = (700 * 2) / (8.31 * 450)
= 1400/3739.5
= 0.34
Please somone help me with a chemistry question brainliest to whoever answers correctly and 20 points
Answer:
3132 is the answer
Explanation:
3BaCl2 + Al2S3 → 3BaS + 2AlCl3
Answer:
Explanation:
Hope this helps u !!
A reaction requires 22.4 L of gas at STP . There are 25.0 L of gas at 101.5 kPa and 373 K.
Which statement is true?
Use the ideal gas law: PV = nRT where R = 8.31 L-kPa/mol-K
A. There is not enough gas for the reaction.
B. Given this information, there is no way to tell if there is enough gas for the reaction.
C. There is excess gas for the reaction.
D. There is enough gas for the reaction.
Answer:
STP is 101.325 kPa pressure and 273K temperature
Also, at STP, 1 mol of an ideal gas = 22.4 L
Since the question states that 22.4 L are needed at STP, we know that ONE MOLE is needed. Now, the question is, how many moles are actually present?
V = 25.0 L
P = 101.5 kPa
T = 373K
n = ?
R = 8.31 L-kPa/Kmol
Solving the ideal gas law for n (moles) and comparing that to 1 mole, we have...
n = PV/RT = (101.5)(25.0)/(8.31)(373)
n = 0.82 moles of gas. THIS IS NOT ENOUGH as it is less than the ONE mole required.
Explanation:
Para la siguiente reacción: 2NH 3(g) + CO 2(g) ———> (NH 2 ) 2 CO (l) + H 2 O (l) a) ¿Cuántos gramos de NH 3 se necesitan para formar 720 g de (NH 2 ) 2 CO? b) ¿Cuántos moléculas de agua se obtienen a partir de 9 litros de CO 2 ayudenme porfa
Answer:
a. 408g de NH3 son necesarios
b. 2.42x10²³ moléculas de agua se obtienen
Explanation:
a. Basados en la reacción, 2 moles de NH3 producen una mol de (NH2)2CO. Para resolver esta pregunta debemos convertir la masa de (NH2)2CO a moles. Estas moles a moles de NH3 y su respectiva masa:
Moles (NH2)2CO -Masa molar: 60.06g/mol-
720g * (1mol / 60.06g) = 11.99 moles (NH2)2CO
Moles NH3:
11.99 moles (NH2)2CO * (2mol NH3 / 1mol (NH2)2CO) = 23.98 moles NH3
Masa NH3 -17.031g/mol-:
23.98 moles NH3 * (17.031g / mol) = 408g de NH3 son necesarios
b. 1mol de CO2 produce 1mol de agua. Se debe convertir el volumen a moles usando PV = nRT. Estas moles = Moles de agua. 1mol = 6.022x10²³ moléculas:
Asumiendo STP:
PV = nRT; PV / RT = n
Donde P = 1atm a STP
V = 9L
R = 0.082atmL/molK
T = 273.15K a STP
1atm*9L / 0.082atmL/molK*273.15K = n
n = 0.402 moles CO2 = Moles H2O
Moléculas:
0.402 moles agua * (6.022x10²³ moléculas / 1mol) =
2.42x10²³ moléculas de agua se obtienenHow does anatomy provide evidence for evolution?
I'll give brainlist!! Simple answer please.
What is created when electrons become detached from their local atom?'
a) An Atom
b) Cation
c) Anion
d) Delocalized electrons
Answer:
B. Cation
Explanation:
As an electron is removed from the atom it is then converted into a positively charged ion known as a Cation.
Hope this helps u
Calculate the volume of this regular solid.
What is the volume of the rectangular prism?
1
6 cm
5 cm
9 cm
what happened to the ionization energy of hydrogen"H" when its electron affinity
A circuit is set up with two parallel resistors, each of a resistance of 250Ω.
b. If another resistor of resistance 300Ω is added in series with these two parallel resistors, what is the total
resistance?
c. If a voltage of 120V is put across the circuit in b, what will the current be in the circuit?
Answer:
425 and 0.28A
Explanation:
Resistance for resistors in parallel
1/ R = 1/250 +1/250
=0.008
R = 1/ 0.008 = 125
Total resistance
R= 125+ 300
=425
...
V= IR
I= V/R
I = 120/425
= 0.28 A
Fossil fuels are considered to be:
a.
irreplaceable resources
c.
renewable resources
b.
nonrenewable resources
d.
hazardous wastes
Please select the best answer from the choices provided
A
B
C
D
If you have 3 moles of a gas at a pressure of 2.5 atm and a volume of 8 liters, what is the temperature?
a. 57.86 K
b. 0.81 K
c. 25 K
d. 81.26 K
Answer:
d
Explanation:
pv=nrt
2.5×1.01×10^5×8×10^-3=3×8.31×T
T=
The value of the temperature can be determined by ideal gas law and the temperature will be 0.81 K.
What is temperature ?The average kinetic energy of particular atoms and molecules in a system is measured by the temperature.
What is ideal gas Law?
Ideal gas law explain the relationship between pressure. temperature and volume.
Ideal gas law can be expressed as, PV=nRT.
where, P is pressure. V is volume , n is number of moles ,R is gas constant and T is temperature. It is given that, n= 3 mole, P = 2.5 atm, V = 8 L, T=?, R = 8.31.
Calculation of temperature by using ideal gas law is shown as:
Now, put the values of given data in ideal gas law equation.
T = PV/nR
=2.5×8/3×8.32
= 0.81 K
Therefore, the temperature will be 0.81K.
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What species is reduced in the reaction below?
Zn° + 2 Ag+ → Zn2+ + 2 Agº?
A) Znº
B) Agº
C) Zn2+
D) Ag+
Answer: The correct option is D) [tex]Ag^+[/tex]
Explanation:
The oxidation reaction is defined as the reaction in which a chemical species loses electrons in a chemical reaction. It occurs when oxidation number of a species increases.
A reduction reaction is defined as the reaction in which a chemical species gains electrons in a chemical reaction. It occurs when oxidation number of a species decreases.
For the given chemical reaction:
[tex]Zn^0+2Ag^+\rightarrow Zn^{2+}+2Ag^0[/tex]
On the reactant side:
Oxidation number of Zn = 0
Oxidation number of Ag = +1
On the product side:
Oxidation number of Zn = +2
Oxidation number of Ag = 0
As the oxidation number of Ag is decreasing from +1 to 0. Thus, [tex]Ag^+[/tex] is getting reduced.
Hence, the correct option is D) [tex]Ag^+[/tex]
What is stoichiometry?
Answer:
hope it help u !!!!
Explanation:
Stoichiometry is the relationship between the relative quantities of substances taking part in a reaction or forming a compound, typically a ratio of whole integers
how many grams are represented by 1.45 moles of Koh? Determine your answer to the correct number of significant figures.
Answer:
[tex]\boxed {\boxed {\sf 81.4 \ g\ KOH}}[/tex]
Explanation:
We are asked to convert 1.45 moles of potassium hydroxide (KOH) to grams.
1. Molar MassThe molar mass is the mass in grams of 1 mole of a substance. The values are found on the Periodic Table. They are the same as the atomic masses but the units are grams per mole (g/mol) instead of atomic mass units (amu).
We have the compound KOH. Look up the molar masses of the individual elements.
Potassium (K): 39.098 g/mol Oxygen (O): 15.999 g/mol Hydrogen (H): 1.008 g/molThe formula for the compound has no subscripts, so there is 1 mole of each element in 1 mole of the compound. We can simply add the molar masses.
KOH: 39.098 + 15.999 + 1.008 =56.105 g/mol2. Convert Moles to GramsBased on the molar mass, there are 56.105 grams of KOH in 1 mole. Create a ratio using this information.
[tex]\frac {56.105 \ g\ KOH}{ 1 \ mol \ KOH}[/tex]
We are converting 1.45 moles of KOH to grams, so we multiply by this value.
[tex]1.45 \ mol \ KOH *\frac {56.105 \ g\ KOH}{ 1 \ mol \ KOH}[/tex]
The units of moles of KOH cancel.
[tex]1.45\ *\frac {56.105 \ g\ KOH}{ 1 }[/tex]
[tex]81.35225 \ g\ KOH[/tex]
3. RoundThe original measurement of moles has 3 significant figures, so our answer must have the same.
For the number we calculated, that is the tenths place. The 5 in the hundredths place (81.35225) tells us to round the 3 up to a 4.
[tex]81.4 \ g\ KOH[/tex]
Approximately 81.4 grams of potassium hydroxide are represented by 1.45 moles.
The table shows the specific heat of four substances—brick, dry soil, paper, and water. If all four substances were exposed to sunlight for the same amount of time, which substance would heat up the fastest?
Answer:
Brick
Explanation:
.................
Directions: Each set of lettered choices below refers to the numbered statements immediately following it. Select the one lettered choice that best fits each statement. A choice may be used once, more than once, or not at all in each set. The following questions refer to the below molecules: (A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3 The molecule that has trigonal pyramidal geometry
Answer:
The given molecules are:
(A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3
Which one has trigonal pyramidal geometry?
Explanation:
According to VSEPR (valence shell electron pair repulsion) theory, a molecule with a central atom having hybridization sp3 and with one lone pair of electrons has trigonal pyramidal geometry.
Among the given molecules,
CO2 has central atom carbon with sp hybridization without lone pairs.
So, it is a linear molecule.
H2O, the central atom is oxygen with sp3 hybridization and oxygen has two lone pairs. So, its geometry is V-shape or bent.
CH4 has central atom carbon with sp3 hybridization and no pairs.
So, its geometry is tetrahedral.
C2H4 ethene has carbon atoms as the central atoms with sp2 hybridization and carbon has no lone pairs.
So, its geometry is trigonal planar.
Answer:
PH3 has central atom P with sp3 hybridization.
P has one lone pair on it.
Hence, the geometry of PH3 is trigonal pyramidal.
Magnesium is added to dilute hydrochloric acid. This makes bubbles of hydrogen and a colorless solution of magnesium chloride. Write down the name of one of the products of this reaction.
Answer:
The products are already in the question Hydrogen gas and Magnesium Chloride
Explanation:
2Mg +2HCl₂ = 2MgCl₂ + H₂ balanced equation if you need it
When any metal react with acid then salt and hydrogen gas is formed. Hydrogen gas and Magnesium Chloride are formed when Magnesium is added to dilute hydrochloric acid.
What is chemical reaction?Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.
The products are Hydrogen gas and Magnesium Chloride. The balanced equation can be written as
Mg +2HCl[tex]\rightarrow[/tex] MgCl₂ + H₂
This makes bubbles of hydrogen and a colorless solution of magnesium chloride.
Therefore Hydrogen gas and Magnesium Chloride are formed when Magnesium is added to dilute hydrochloric acid.
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The atoms of elements A (blue) and B (orange) form 2 compounds shown here. Do these compounds obey the law of multiple proportions?
Hello. You have not presented the image that presents the two elements mentioned in the question. This makes it impossible for your question to be answered. However, I will try to help you as best I can.
To say whether the compounds obey the law of multiple proportions, you should observe whether one of the elements, formed from the compounds, maintains a fixed mass, while the other element presents the mass in a varied amount of small, whole numbers, spread across the formed compounds .
This is because the law of multiple proportions states that an element must have a fixed mass when reacting with another element to create compounds. This reaction will allow this element to keep the mass fixed, while the other element will generate different compounds, where each one presents a part of the mass of the forming element, in small and whole numbers.
Identify the total number of moles involved in the reaction
2C4H10(g) + 13 O2(g) – 10 H2O(g) + 8 CO2(g)
Answer:
33 moles
Explanation:
The given chemical reaction is 2C₄H₁₀(g) + 13 O₂(g) → 10H₂O(g) + 8CO₂(g)
The number of moles of each reactant are as follows;
Butane, C₄H₁₀ = 2 moles of (g) + 13 (g) → 10H₂O(g) + 8CO₂(g)
Oxygen gas, O₂ = 13 moles
Water, H₂O = 10 moles
Carbon dioxide, CO₂ = 8 moles
The total number of moles, n = (2 + 13 + 10 + 8) = 33
∴ The total number of moles involved in the reaction, n = 33 moles.
calculate the pressure in atm of .68 mol of H at 298K and occupying 4.5 L
Answer:
3.7 atm
General Formulas and Concepts:
Atomic Structure
MolesGas Laws
Ideal Gas Law: PV = nRT
P is pressureV is volumen is number of molesR is gas constantT is temperatureExplanation:
Step 1: Define
Identify variables
[Given] n = 0.68 mol H
[Given] T = 298 K
[Given] V = 4.5 L
[Given] R = 0.0821 L · atm · mol⁻¹ · K⁻¹
[Solve] P
Step 2: Find Pressure
Substitute in variables [Ideal Gas Law]: P(4.5 L) = (0.68 mol)(0.0821 L · atm · mol⁻¹ · K⁻¹)(298 K)Multiply [Cancel out units]: P(4.5 L) = (0.055828 L · atm · K⁻¹)(298 K)Multiply [Cancel out units]: P(4.5 L) = 16.6367 L · atmIsolate P [Cancel out units]: P = 3.69705 atmStep 3: Check
Follow sig fig rules and round. We are given 2 sig figs as our lowest.
3.69705 atm ≈ 3.7 atm
Beryllium is in Group 2.
What does this tell you about the electronic structure of beryllium?
Answer:
[He] 2s²
Explanation:
ASAAAP HURRRY PLS!!!
Where in aerobic respiration is the largest amount of energy produced?
A)
At the beginning of the cycle, when glucose is oxidized to pyruvate.
B)
At the end of the electron transport chain, when oxygen is reduced.
C)
At the end of the electron-transport chain, when oxygen is oxidized.
D)
At the beginning of the electron transport chain, when oxygen is oxidized.
Cells can regulate different processes in two ways. They can turn on and off the genes that make enzymes, or they can
A)
increase the activation energy of a reaction.
B)
increase the amount of energy needed to carry out the preferred process.
C)
regulate the enzymes that are already made.
D)
decrease the amount of energy needed to carry out the preferred process.
HELP PLEASEEEEE HURRY!!
Answer:
The answer is c
