Answer:
bronze, copper
Explanation:
bronze is used to make medals and carve statues
copper is used to make wire and utensils
Calculate the number of O atoms in 0.364 g of CaSO4 · 2H2O
Answer:
= 7.66 x 10²¹ oxygen atoms in 0.364 grams of CaSO₄·2H₂O
Explanation:
For problems like this posting, one needs an understanding of the following topics:
The definition of the mole
1 mole of substance = mass in grams of substance containing 1 Avogadro's Number ( = 6.023 x 10²³ ) of particles of the specified substance. This is generally one formula weight of the substance of interest. From this, the following equivalent relationships should be memorized:
1 mole = 1 formula weight = 1 mole weight (g)= 6.023 x 10²³ particles
Converting grams to moles:
Given grams => moles = grams/gram formula wt
Converting moles to grams:
Given moles => grams = moles x gram formula wt
_________________________________________________________
Calculate the number of O atoms in 0.364 g of CaSO₄ · 2H₂O.
Given mass CaSO₄ · 2H₂O = 0.364 grams
Formula Wt CaSO₄ · 2H₂O = 172 g/mole
moles CaSO₄ · 2H₂O = mass CaSO4 · 2H2O / formula Wt. CaSO₄ · 2H₂O
= 0.364 g CaSO₄·2H₂O / 172 g CaSO4·2H2O
= (0.364/172) mole CaSO₄·2H₂O
= 2.12 x 10⁻³ mole CaSO₄·2H₂O
∴ number of Oxy (O) atoms in 0.364 grams CaSO₄·2H₂O
= (2.12 x 10⁻³ mole CaSO₄ · 2H₂O)(6.023 x 10²³ molecules CaSO₄· 2H₂O/ mole)
= 1.276876 x 10²¹molecules CaSO₄· 2H₂O CaSO₄2H₂O
= 1.276876 x 10²¹ molecules CaSO₄· 2H₂O x 6 oxygen atoms / molecule
= 7.661256 x 10²¹ oxygen atoms in 0.364 grams of CaSO₄·2H₂O
= 7.66 x 10²¹ oxygen atoms in 0.364 grams of CaSO₄·2H₂O
An earthquake occurs at 8:15:35 PM, and a seismic station detects the P-
wave at 8:20:05 PM. What was the travel time for the P-wave to this
seismic station? *
- 3 minutes and 30 secs
-4 minutes and 30 secs
-5 minutes and 30 secs
-6 minutes and 30 secs
Answer:
5 minutes 35 seconds because an earthquake travels underground faster than on the surface
Which group on the periodic table contains chemical elements that are shiny and conduct electricity?
A.
Metalloids
B.
Nonmetals
C.
Representative elements
D.
Metals
A gas occupies 0.67 L at 350 K. What temperature is required to reduce
the volume to 0.21 L *
Answer:
109.7K
Explanation:
Using Charles law equation as follows;
V1/T1 = V2/T2
Where;
V1 = initial volume (L)
V2 = final volume (L)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the information provided in this question;
V1 = 0.67L
V2 = 0.21L
T1 = 350K
T2 = ?
Using the formula above;
0.67/350 = 0.21/T2
0.001914 = 0.21/T2
0.001914T2 = 0.21
T2 = 0.21/0.001914
T2 = 109.7K
A boulder rests on a ledge 31.2 m above a lake. If it has 2.65 x 10 J of gravitational
potential energy relative to the lake surface, what is the mass of the boulder?
Answer:
This question is incomplete, the gravitational potential energy is 2.65 x 10^5 J
mass of the boulder = 866.7g
Explanation:
Potential energy (P.E) refers to the energy due to the position of a body. It can be calculated as follows:
P.E = m × g × h
Where;
m = mass of substance (g)
g = acceleration due to gravity (m/s²)
h = height (m)
According to the information provided in this question,
h = 31.2 m
g = 9.8m/s²
m = ?
P.E = 2.65 x 10^5 J
Using P.E = m × g × h
2.65 x 10^5 = m × 9.8 × 31.2
2.65 x 10^5 = 305.76m
265000 = 305.76m
m = 265000 ÷ 305.76
m = 866.69
mass of the boulder = 866.7g
is silicone malleable or brittle
Answer:
Luster: Silicon for example appears lustrous, but is not malleable or ductile (it is brittle - a characteristic of some nonmetals). It is a much poorer conductor of heat and electricity than the metals.8 May 2021
Elements: Oxygen; Carbon
Explanation:
hope it helps
un estudiante introduce un corcho cuya densidad es 0.95 g/cm en cada uno de los liquidos que figura representa mejor la situacion
Answer:
La respuesta correcta es la opción A.
Explicación:
La densidad del corcho es 0.95g / cm3 por lo que se hundirá en la solución de acetona porque el corcho es más denso que la solución de acetona mientras que por otro lado, el corcho flotará en otros dos líquidos porque la densidad del corcho es menor que en otros dos líquidos o, en otras palabras, los dos líquidos son más densos que el corcho, por eso el corcho flotará en estos dos líquidos.
What is the speed of a wave that has a frequency of 220 Hz and a wavelength
of 0.39 m?
A. 0.002 m/s
B. 564 m/s
C. 85.8 m/s
D. 0.01 m/s
Answer:
12d
Explanation:
1. A(n) bond forms when one atom gives up one or more electrons to another atom. 2. Atoms or molecules with a net electric charge due to the loss or gain of one or more electrons are . 3. A(n) bond involves the sharing of electron pairs between atoms, also known as a molecular bond. 4. When one pair of electrons is shared between two atoms, a bond is formed. 5. When two pairs of electrons are shared between two atoms, a bond is formed. 6. A bond is a type of chemical bond where a pair of electrons is unequally shared between two atoms. As a result, one end of the molecule has a slightly negative charge and the other a slightly positive charge.
Answer:
For 1: Ionic
For 2: Ions
For 3: Covalent
For 4: Single
For 5: Double
For 6: Polar
Explanation:
For 1:An ionic compound is formed when the complete transfer of electrons takes place from one element usually, metals (forming cation) to another element usually, non-metals (forming anions).
Hence, an ionic bond forms when one atom gives up one or more electrons to another atom
For 2:An ion is formed when an element loses or gains an electron. Two types of ions are formed which are cations and anions.
Hence, atoms or molecules with a net electric charge due to the loss or gain of one or more electrons are ions.
For 3:A covalent bond is defined as the bond which is formed by the sharing of electrons between two atoms.
Hence, a covalent bond involves sharing electron pairs between atoms, also known as a molecular bond.
For 4:A single bond is defined as the bond in which 1 bond is present between the two atoms or 1 pair of electrons (two electrons) are shared between the atoms.
Hence, when one pair of electrons is shared between two atoms, a single bond is formed.
For 5:A double bond is defined as the bond in which 2 bonds are present between the two atoms or 2 pairs of electrons (four electrons) are shared between the atoms.
Hence, when two pairs of electrons are shared between two atoms, a double bond is formed
For 6:A polar bond is defined as the bond where unequal sharing of electrons takes place. This creates a dipole within a molecule.
Hence, a polar bond is a type of chemical bond where a pair of electrons is unequally shared between two atoms.
19
Gold reacts with the elements in Group 7 of the periodic table.
0.175 g of gold reacts with chlorine.
The equation for the reaction is:
2 Au + 3 Cl2 - 2 AuCla
Calculate the mass of chlorine needed to react with 0.175 g of gold.
Give your answer in mg
Relative atomic masses (Ar): Cl = 35.5 Au = 197
Answer: The mass of chlorine gas required is 94.6 mg
Explanation:
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
Given mass of gold = 0.175 g
Molar mass of gold = 197 g/mol
Plugging values in equation 1:
[tex]\text{Moles of gold}=\frac{0.175g}{197g/mol}=0.000888 mol[/tex]
The given chemical equation follows:
[tex]2Au+3Cl_2\rightarrow 2AuCl_3[/tex]
By the stoichiometry of the reaction:
If 2 moles of gold reacts with 3 moles of chlorine gas
So, 0.000888 moles of gold will react with = of chlorine gas
Molar mass of chlorine gas = 71 g/mol
Plugging values in equation 1:
[tex]\text{Mass of chlorine gas}=(0.001332mol\times 71g/mol)=0.0946g=94.6mg[/tex] (Conversion factor: 1 g = 1000 mg)
Hence, the mass of chlorine gas required is 94.6 mg
17. (1.09 x 102) x (2.79 x 10')
18. (5.75 x 104) / (4.71 102)
19.(3.38 x 106) x (7.80 x 104)
20. (7.04 x 10) / (9.45 x 10-)
Answer:
17. 3,101.922
18. 1.2447441822
19. 288,057.12
20. 0.74497354
Standardization of a Borax solution (Na2B4O7). You are given a 1.044 M solution of H2SO4. It takes 2.63 mL of this H2SO4 to reach the end point. Knowing it takes 1 H2SO4 to neutralize 2 Na2B4O7, what was the concentration of this Borax solution?
The question is incomplete, the complete question is:
Standardization of a Borax solution (Na2B4O7). A student titrates a 20.00 mL sample of an aqueous borax solution with 1.044 M H2SO4. It takes 2.63 mL of acid to reach the equivalence point. Knowing it takes 1 H2SO4 to neutralize 2 Na2B4O7, what was the concentration of this Borax solution?
Answer: The concentration of borax solution is 0.069 M.
Explanation:
To calculate the concentration of borax solution, the formula used is:
[tex]n_1C_1V_1=n_2C_2V_2[/tex] ....(1)
where,
[tex]n_1, C_1\text{ and }V_1[/tex] are the n-factor, concentration and volume of sulfuric acid
[tex]n_2,C_2\text{ and }V_2[/tex] are the n-factor, concentration and volume of borax solution.
We are given:
[tex]n_1=1\\C_1=1.044M\\V_1=2.63mL\\n_2=2\\C_2=?M\\V_2=20mL[/tex]
Putting values in equation 1, we get:
[tex]1\times 1.044\times 2.63=2\times C_2\times 20\\\\C_2=\frac{1\times 1.044\times 2.63}{2\times 20}\\\\C_2=0.069M[/tex]
Hence, the concentration of borax solution is 0.069 M.
Fig. 6.1 shows the structural formula of an organic compound.
Fig. 6.1 (a) Name any two functional groups presents in the compound. (b) Give the structure of the organic product formed when the compound is reacted with Brz in an inert solvent, (ii) hot concentrated KMnO4, Na solid, (iv) CH3COCI benzenediazonium salt. (c) State the observations made in each of the reactions in each reaction in b
Answer:
A dono wat is da anser sori man hehe
Answer:
(a).
→ Hydroxyl group.
→ Carbon-carbon double bond. ( alkene )
→ Esters.
(c).
(I). A colourless solution : with bromine atoms on cyclo hexene.
or: A white precipitate due to bromine atoms formed on phenol.
(ii). The purple solution turns colourless due to oxidation of the cyclo hexene.
(iii).
Bubbles of a colourless gas ( hydrogen gas ) formed when sodium reacts with the hydroxyl group to form Sodium oate ions.
(iv). Am not sure about my answer.
(v).
A red dye is formed. ( and azo dye is formed due to benzenediazonium salt reacting with phenol ).
QUESTION ABOUT IONIC COMPUND DUE IN 7 MINUTES URGENT!!!!!!!!!!!!!
Answer:
NH2S4. . ...............................,..
types of molecular forces
Answer:
Hydrogen bonds
Covalent bonds
Van Der Walls Forces
Ionic Bonding
London Dispersion forces
Metallic bonding
Chemical bonds
When does carbon dioxide absorb the most heat energy?
during freezing
during deposition
during sublimation
during condensation
Answer:
it happenes during sublimation
Answer:
C
Explanation:
Edg
What is the value of Keq for the reaction expressed in scientific notation? 1.6 ´ 10–5 6.2 ´ 10–4 6.2 ´ 104 1.6 ´ 105
The question is incomplete, the complete question is:
Consider the reaction:
[tex]2NOCl\rightleftharpoons 2NO+Cl_2[/tex]
At equilibrium, the concentrations are as follows. [NOCl] = 1.4 × 10–2 M [NO] = 1.2 × 10–3 M [Cl2] = 2.2 × 10–3 M What is the value of Keq for the reaction expressed in scientific notation?
A) 1.6 × 10–5
B) 6.2 × 10–4
C) 6.2 × 10+4
D) 1.6 × 10+5
Answer: The correct option is A) [tex]1.6\times 10^{-5}[/tex]
Explanation:
The equilibrium constant is defined as the ratio of the concentration of products to the concentration of reactants raised to the power of the stoichiometric coefficient of each. It is represented by the term [tex]K_{eq}[/tex]
For the given chemical equation:
[tex]2NOCl\rightleftharpoons 2NO+Cl_2[/tex]
The expression for equilibrium constant will be:
[tex]K_{eq}=\frac{[NO]^2}{[Cl_2][NOCl]^2}[/tex]
Given values:
[tex][NO]=1.2\times 10^{-3}M[/tex]
[tex][Cl_2]=2.2\times 10^{-3}M[/tex]
[tex][NOCl]=1.4\times 10^{-2}M[/tex]
Putting values in above expression, we get:
[tex]K_{eq}=\frac{(1.2\times 10^{-3})^2\times (2.2\times 10^{-3})}{(1.4\times 10^{-2})^2}\\\\K_{eq}=1.6\times 10^{-5}[/tex]
Hence, the correct option is A) [tex]1.6\times 10^{-5}[/tex]
2. What is the name of the lens of a microscope through which the image is viewed?
a. objective
c. diaphragm
b. eyepiece
d. stage
Answer:
b
Explanation:
the ocular lens or eyepiece lens ...so its b
For the reaction C + 2H2 → CH4, how many moles of hydrogen are needed to make 192.3 grams of methane, CH4?
Answer:
24
Explanation:
A 125 mL sample of phosphoric acid was titrated with an average of 63.7 mL of a 0.050M barium hydroxide solution according to the given reaction: 2 H3PO4 + 3 Ba(OH)2 ⇌ Ba3(PO4)2 + 6 H2O Determine the concentration of the phosphoric acid sample:
Answer:
0.017 M
Explanation:
The balanced equation for the reaction is given below:
2H₃PO₄ + 3Ba(OH)₂ ⇌ Ba₃(PO₄)₂ + 6H₂O
From the balanced equation above,
The mole ratio of acid, H₃PO₄ (nₐ) = 2
The mole ratio of base, Ba(OH)₂ (n₆) = 3
Finally, we shall determine the concentration of the phosphoric acid, H₃PO₄. This can be obtained as follow:
Volume of acid, H₃PO₄ (Vₐ) = 125 mL
Volume of base, Ba(OH)₂ (V₆) = 63.7 mL
Concentration of base, Ba(OH)₂ (C₆) = 0.050M
Concentration of acid, H₃PO₄ (Cₐ) =?
CₐVₐ / C₆V₆ = nₐ/n₆
Cₐ × 125 / 0.05 × 63.7 = 2/3
Cₐ × 125 / 3.185 = 2/3
Cross multiply
Cₐ × 125 × 3 = 3.185 × 2
Cₐ × 375 = 6.37
Divide both side by 375
Cₐ = 6.37 / 375
Cₐ = 0.017 M
Thus, the concentration of the phosphoric acid, H₃PO₄ is 0.017 M
Nombra cada uno de los siguientes hidrocarburos de acuerdo a las reglas de la IUPAC
Answer:
i) ciclobutano
ii) 3-etil-4-metil ciclopenteno
Explanation:
Toda la idea de la nomenclatura IUPAC es permitir que la estructura de la sustancia se derive de su nombre y viceversa.
La nomenclatura IUPAC es un sistema universalmente aceptado para nombrar compuestos químicos.
los nombres de los compuestos enumerados son;
i) ciclobutano
ii) 3-etil-4-metil ciclopenteno
Iron oxide reacts with aluminum to give aluminum oxide and iron, what kind of chemical is this?
A) Combustion
B) decomposition
C) replacement
D) synthesis
Answer:
[tex]{ \tt{c). \: replacement}}[/tex]
C) replacement
Iron(III) oxide (Fe2O3) reacts with aluminium(Al) to form aluminium oxide(Al2O3) and molten iron(Fe). This is a replacement reaction
Can anyone plz explain me this
Answer:
A. Cl2(g) + 2NaBr(aq) --> 2NaCl(aq) + Br2(g)Explanation:
This is because,
Chlorine atoms (Cl2) displaces with Bromine atoms (Br) in Sodium bromide (2NaBr) solution to give a result as, Sodium Chloride (2NaCl) and left out atom Bromine (Br)
what do u understand by the word
ATOM
Answer:
An atom is a particle of matter that uniquely defines a chemical element . An atom consists of cental nucleus that is usually surrounded by one or more electrons. Each electrons is negatively charged.
Hope this helps you! bye
H2SO4 +HI → __ H2S+12 +H2O balance the equation
Answer:
H2SO4 + 8HI → H2S + 4I2 + 4H2O
Question 9 of 10
Which functional group does the molecule below have?
Answer:
Hydroxyl
Explanation:
A P E X
Hãy tìm công thức hóa học của những oxit có thành phần khối lượng như sau S:50%; C:42,8%; Mn:49,6%; Pb:86,6%
Answer:
Find the chemical formulas of oxides that contain the following composition:
S:50%; C:42,8%; Mn:49,6%; Pb:86,6%
Explanation:
In the given oxide of sulphur,
50%S is present that means remaining 50% is O.
Divide the % with atomic mass:
S O
50/32= 1.5625 50/16=3.125
divide with smallest ratio:
1.5625/1.5625=1 3.125/1.5625=2
Hence, the formula of oxide is [tex]SO_2[/tex].
Similarly:
Carbon is 42.8% means the reamining % will be O that is 57.2%.
C O
42.8/12=3.575 57.2/16=3.575
Divide with smallest ratio:
3.575/3.575=1 3.575/3.575=1
Hence, the formula of oxide is CO.
Mn is 49.6% means the remining is % is O that is 50.4%.
First divide with atmic mass of respective element, then get the smallest ratio.
That gives the mole ratio of each constituent atom.
Mn O
49.6/55.0=0.90 50.4/16=3.15
0.90/0.90=1 3.15/0.90=3.5
Multiply with two
2 7
Hence, the formula becomes:
[tex]Mn_2O_7[/tex]
Pb is 86.6% means ---remaining 13.4% is O.
Pb O
86.6/207 = 0.418 mol 13.4/16=0.85
0.418/0.418=1 0.85/0.418=2.0
Hence, the formula is:[tex]PbO_2[/tex]
You've made a hot drink by dissolving a teaspoon of instant coffee and a teaspoon of sugar in a cup of hot water. Which of the following statements is true? Group of answer choices The water is the solute portion of the drink. The instant coffee and sugar dissolve because they have no charged regions to repel the partial positive and partial negative regions of the water molecules. The instant coffee and sugar are solvents. You've just prepared an aqueous solution.
Answer: The statement, you've just prepared an aqueous solution is true.
Explanation:
When one or more number of substances are dissolved in a solvent like water then solution formed is called an aqueous solution.
For example, when a hot drink is made by dissolving a teaspoon of instant coffee and a teaspoon of sugar in a cup of hot water is an aqueous solution.
Here, both coffee and sugar are solute whereas hot water is the solvent.
Thus, we can conclude that the statement, you've just prepared an aqueous solution is true.
How many molecules are present in this sample
0.423 mol co
Pottery and china are suitable for making tea pots because they are:
brittle.
transparent
heat insulators.
non-conductors of electricity.
Quick help me
Answer:
non-conductors of electricity.
Explanation:
One of the auxiliary pleasures of drinking tea is selecting accoutrements: utensils, cups, kettles, storage tins, and, of course, teapots. The choices are legion with a dazzling array of shapes, sizes, decorative touches. Sometimes that blinds us to one of the most important decisions we must make in teapot selection: its function!
One of the auxiliary pleasures of drinking tea is selecting accoutrements: utensils, cups, kettles, storage tins, and, of course, teapots. The choices are legion with a dazzling array of shapes, sizes, decorative touches. Sometimes that blinds us to one of the most important decisions we must make in teapot selection: its function!Your teapot-buying decision should be based first and foremost on size (options often go from one to six cups, sometimes larger). The next most important aspects are your personal preference for material (glass, ceramic or porcelain) and whether it will be used for brewing tea or pouring brewed tea. Other important factors include: whether it's easy to hold, pours well, and, of course, fits into your budget. A gigantic Majolica pot, festooned with monkeys and in a brilliant highly-glazed green, may warm your heart; but if when filled with tea it weighs five pounds and holds more than your family can drink, it will probably be better suited for the collector�s shelf than the tea table.
brainly me pls