Answer:
ExplaAt high temperatures MgCO3 decomposes to magnesium oxide and carbon dioxide. This process is important in the production of magnesium oxide. This process is called calcining: MgCO3 → MgO + CO2 (ΔH = +118 kJ/mol)
nation:
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
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
Which group on the periodic table contains chemical elements that are shiny and conduct electricity?
A.
Metalloids
B.
Nonmetals
C.
Representative elements
D.
Metals
H2SO4 +HI → __ H2S+12 +H2O balance the equation
Answer:
H2SO4 + 8HI → H2S + 4I2 + 4H2O
An ideal gas is a gas.
Perfect
Theoretical
Real
Answer:
An ideal gas is a theoretical gas composed of many randomly moving point particles that are not subject to interparticle interactions. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics.
An ideal gas is theoretical
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.
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:
Which statements are true of the reaction below? 2Na(s) + Cl2(g) ---> 2NaCl(s)

A.
Na(s) is a reactant.

B.
NaCl is a product.

C.
NaCl is a liquid.

D.
Cl2 is a solid.
Answer:
A and B are both true
Explanation:
Na is REACTING with Cl2 to PRODUCE NaCl
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]
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.
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 ).
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
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)
5. Discuss the phenomena of sunrise and sunset seen on Earth and describe how they will be different from the perspective of outer space. PLS IM OFFERING 15 POINTS PLSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS
Answer:
deez
Explanation:
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
Which best describes a mixture?
It has a single composition, and it has a set of characteristics that does not change.
O It can have different compositions, but it has a set of characteristics that does not change.
O It has a single composition, but it has a set of characteristics that does change.
It can have different compositions, and it has a set of characteristics that does change.
Mark this and return
Save and yit
Answer:
I think the answer would be b, sorry if I'm wrong(EDIT: ITS ACTUALLY AAAAA)
ways to manage non-biodegradable waste wisely
Answer:
Non-biodegradable wastes can be managed by practicing the concept of 3Rs—Reduce, Reuse, and Recycle.
...
Management Of Non-Biodegradable Wastes
Use fountain pen in place of a ballpoint pen,
Use old newspapers for packaging, and.
Use cloth napkins in place of disposable ones.
Explanation:
there!
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 qué se refiere cuando se dice que el trabajo científico es cualitativo y cuantitativo? Por favor
Answer:
ver explicacion
Explanation:
La investigación cualitativa tiene que ver con la investigación que implica la recopilación de datos no numéricos, mientras que la investigación cuantitativa tiene que ver con la recopilación de datos numéricos.
La investigación científica a menudo tiene que ver con la observación y la realización de inferencias. Este aspecto de la investigación científica es cualitativo.
Al mismo tiempo, es posible que también se requieran gráficos, tablas y cuadros para la presentación de datos en ciertos tipos de investigación científica. Esta es ahora una investigación cuantitativa.
Por tanto, la investigación científica es tanto cualitativa como cuantitativa
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
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.
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]
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
Help, quick, pls
What is a displacement reaction?
[tex]\begin{aligned} -5x+4y &= 3\\\\ x&=2y-15 \end{aligned}[/tex]
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
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
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
Question 9 of 10
Which functional group does the molecule below have?
Answer:
Hydroxyl
Explanation:
A P E X
QUESTION ABOUT IONIC COMPUND DUE IN 7 MINUTES URGENT!!!!!!!!!!!!!
Answer:
NH2S4. . ...............................,..
Which statement best describes why industry uses heterogeneous catalysts?
They tend to be more stable.
They are all gases at room temperature.
They form strong bonds with reactant molecules.
They cause stronger bonds to form between molecules.
Answer:
They tend to be more stable
Explanation:
A heterogeneous catalyst is a type of catalyst that exist in a phase which is different from the phases of the reacting mixture or specie or the products and the reactants are absorbed into sites on the catalyst for binding
The heterogeneous catalyst is used in industry because of its main advantage, which is its ease and simplicity of separation from the mixture of the reaction using a straightforward process such as filtration to recover and reuse a costly (heterogeneous) catalyst
Therefore, industry uses the heterogeneous catalyst because the catalyst tend to be more stable and can be easily recovered and reused in its original form
Answer:
A. They tend to be more stable.
Explanation:
Got a 100 on E2020.