write the electronic configuration of the first 20 element
Determine the mass of oxygen in a 45.0 g sample of calcium carbonate
Answer:
The mass of oxygen in 45.0 g sample of calcium carbonate is approximately 21.58 g
Explanation:
The chemical formula for calcium carbonate is CaCO₃
The molar mass of CaCO₃ = 100.0869 g/mol
The mass of oxygen in one mole of CaCO₃ = 3 × 15.999 g = 47.997 g
The mass of oxygen in 45.0 g sample of CaCO₃, m, is goven as follows;
m = 45.0/100.0869 × 47.997 g ≈ 21.58 g
The mass of oxygen in 45.0 g sample of calcium carbonate, m ≈ 21.58 g
What is the difference between a strong base and a weak base?
A. A strong base is always more concentrated than a weak base,
B. A strong base has a lower Ki than a weak base.
C. A strong base produces more ions in solution than a weak base,
D. A strong base is not as conductive as a weak base.
Answer:
C
Explanation:
What are the units of molar mass?
A. L/g
B. mol/g
C. g/L
D. g/mol
SUBST
Answer:
D - g/mol
step by step method
2 Figure 3.1 shows two different forms of carbon, A and B.
A
B
Figure 3.1
a Name the two forms of carbon shown.
Answer:
show the pictures pls specify
step by step of how to convert fahrenheit and celsius to kelvins -5F to kelvins please and thank you
2.
In photosynthesis, which substances are used up, which are produced and which are necessary
but remain unchanged after the reaction?
used up
produced
remain
A
carbon dioxide
water
oxygen
A
8
chlorophylt
carbon dioxide
water
с
oxygen
starch
cellulose
D
water
oxygen
chlorophyll
D. Water is used up, Oxygen is produced and Chlorophyll is necessary, but remains unchanged.
what effect does smiling on at teacher mean when given no homework mean please give me an answer thanks guys
Answer:
no n o n o n o nonono in o no n o n I n jo n b
Explanation:
no no no no no no n on on on I I j
To convert from one metric unit to another metric unit is done simply by moving the decimal place the appropriate amount of places.
Example: 2.5 cm = 25 mm
true or false?
Answer: true
Explanation:
2.5 cm does = 25mm
Answer:
True
Because, all of these metric units differ from one another by a multiple of 10.
Please tell me the answer of what is unit?
Answer:
a quantity chosen as a standard in terms of which other quantities may be expressed.
Explanation:
Explanation:
Unit is a standard physical quantity defined and adopted by convention,with other quantity of same kind.
Which of the following has maximum number of atoms?
(a) 18 g of H2O
(b) 18 g of O2
(c) 18 g of CO2
(d) 18 g of CO4
Answer:
(a) 18 g of H2O
Explanation:
The molecule with great number of moles will have great number of atoms.
By observation, since all compounds have same mass, water has the least molcular mass
[tex]H_{2} O = \: 18 \: g[/tex]
Answer:
18g of H2O
Explanation:
the molecule with great number of moles will have great number of atoms .
(a) option is correct
Compare and contrast qualitative and quantitative data.
Answer: Qualitative data typically consists of words while quantitative data consists of numbers.
Explanation:
Balance the redox reaction by oxidation number or ion electron method and indicate oxidizing and reducing agent . KMno4 + KBr + H2SO4 approach K2SO4 + MnSO4 + H2O + Br2
Answer:
2KMnO₄ (aq) + 10KBr (aq) + 8H₂SO₄ (aq) -> 2MnSO₄ (aq) + 5Br₂ (aq) + 6K₂SO₄ (aq) + 8H₂O (l)
oxidizing agent = KMnO₄
reducing agent = KBr
Explanation:
KMnO₄ -> 2Mn⁷⁺ + 10e⁻ = 2Mn²⁺
KBr -> 10Br⁻⁺ - 10e⁻ = 10Br⁰
cho 3,8g hỗn hợp na2co3 và nahco3 tác dụng với dung dịch hcl.Thoát ra 896 khí ở đktc a/ tính thành phần % theo khối lượng mỗi muối trong hỗn hợp đều.b/ tính thể tích dung dịch hcl 20% biết d= 1,1g trên ml
Answer:
99
Explanation:
it is matter so it and it has.bein 99
Which of the following type of matter has weakest interparticle force of attraction O a. Liquid water
O b. Iron
O c. Steam
O d. sand
Answer:(b)liquid water is correct option . Because it is a molecular solid and molecular solid has weak interparticle forces of attraction
Explanation:
how can you identify if a physical or chemical change has occurred
Answer:
The difference between a physical reaction and a chemical reaction is what its made of. In a chemical reaction, there is a change in the materials of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition. Whereas will a chemical change there is not.
Answer:
Answer:
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds. Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. Some signs of a chemical change are a change in color and the formation of bubbles. The five conditions of chemical change: color chage, formation of a precipitate, formation of a gas, odor change, temperature change. Change in Color. Noticeable Odor (after reaction has begun) Formation of a Precipitate. Formation of Bubbles. Physical changes are changes that do not alter the identity of a substance. Chemical changes are changes that occur when one substance is turned into another substance. Chemical changes are frequently harder to reverse than physical changes
Explanation:
Infrared waves are an example of heat transfer by
A. convection
B. radiation
C. conduction
D. motion of the air
Answer:
convection is my correct answer
list from soft to hard
List the following minerals in order from softest to hardest:
apatite, calcite, talc, quartz, diamond.
Water is dipolar because:
A. It has two hydrogens, each of which pulls oxygen's electrons and separates the
charges into two areas.
B. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a
slight negative and hydrogens a slight positive charge.
C. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a
slight positive and hydrogens a slight negative charge.
OD. It has two hydrogens, each of which has its own polar area.
Answer:
B. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a slight negative and hydrogens a slight positive charge.
Explanation:
In the water molecule (H2O), an oxygen atom is bonded to two hydrogen atoms. Oxygen atom is much more electronegative (has more attraction for electrons) than hydrogen atom, hence, it pulls electrons from one one of the hydrogen atoms bonded to it making it more negatively charged and the hydrogen atom, more positively charged.
The possession of positive charge (+) and negative charge (-) in the same molecule, caused by uneven flow of electrons is what it means to be DIPOLAR (from dipole). Hence, water is DIPOLAR because oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a slight negative and hydrogens a slight positive charge.
A fixed mass of gas has a volume of 92 cm cube and 3 degrees Celsius. What will be its volume at 18 degrees celsius if the pressure remains constant?
Answer:
94.8454
Explanation:
Let volume be V
Let Temperature be T
V1= 92
T1= 3C but to kelvin 273+3= 300K
V2= ?
T2= 18 C but to kelvin 18+273= 291
[tex] \frac{v1}{t1} = \frac{v2}{t2} [/tex]
[tex] \frac{92}{300} = \frac{v2}{291} [/tex]
[tex]v2 \times 300 = 92 \times 291[/tex]
[tex]v2 = \frac{92 \times 291}{300} [/tex]
[tex]v2 = 94.8454[/tex]
Which of the following is an example of a chemical change?
A. Sugar breaking down into water and carbon when it is heated
B. A sugar cube being crushed by a spoon
C. Sugar mixing with red food coloring and forming a red solid
D. A sugar cube dissolving in water as the water is stirred
Answer:
I think its sugar breaking down into watee and carbon when it is heated
I HOPE ITS RIGHT IF NOT THEN SORRYHAVE A GREAT DAY :)
which statement best describes a chemical property of a mineral
Answer:
The mineral forms gas bubbles when a sample is stored in water
Balance in basic solution: O2(g) + Cr³+ (aq) → H₂O2 (1) + Cr₂O7²- (aq)
cr2o72+H2o2-(r3+o2)
Explanation:
r62o72+H2o2-(r3+o2)
solution is an example of______mixtures
Answer:
homogeneous mixture must be the answer
The volume of a gas was 48 mL when the temperature was 159.6 ºC. If the temperature was initially 4.9 ºC, and there was no change in the pressure, what was the initial volume of the gas?
According to Charles law
[tex]\boxed{\sf \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}}[/tex]
[tex]\\ \sf\longmapsto \dfrac{48}{159.6}=\dfrac{V_2}{4.9}[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{48\times 4.9}{159.6}[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{235.2}{159.6}[/tex]
[tex]\\ \sf\longmapsto V_2=1.4mL[/tex]
Determinar el volumen de 20 kg de benceno si su densidad es de 0,88g/cm3
Answer:
volume = mass/ densidad
0.88g/cm3 = 880kg/m3
v=20kg/880kg/m3
v=0.02272727272
o puede ser 0.0227
o tambien puede ser 0.023
b. What chemist finds
out how much nitrogen is in a sample of air
Question 2: thanks!!!
Molar mass calculation for Cl^2
Answer:
Mass of Cl = 35.5
Mass of Cl2 => 35.5×2
=> 71 g/mol
hope that helps ✌
71
explain:The atomic mass of chlorine is equal to the molar mass of chlorine so the molar mass of chlorine is 35.5
=> molar mass for Cl^2: 35,5*2=71
Consider two gases, A and B, which are in a container at room temperature. What effect will the following changes have on the rate of the reaction between these gases?
The temperature is decreased at a constant volume.
A. Increase
B. Decrease
Answer:
A. The rate of reaction will increase or go up
B. The rate of reaction will decrase or go down.
Explanation:
Increasing the temperature will make the gas particles move faster. Faster movement will increase rate of collision between particles to cause a reaction. Decreasing the temperature will cause the opposite to happen.
