Boiling tube containing calcium hydroxide
Answer:
making and testing ammonia/experiment /
Ten gram of hydrated calcium tetra oxo sulphate(vi) ( caso4 × H20 weighs 7.90g after heating and cooling. Calculate the empirical formula of the compound
Answer:
CaSO4. 2H2O
Explanation:
mass of hydrated salt = 10 g
mass of anhydrous salt = 7.90 g
molar mass of hydrated salt = 136 + 18x g/mol
molar mass of anhydrous salt = 136 g/mol
mass of hydrated salt/molar mass of hydrated salt = mass of anhydrous salt/molar mass of anhydrous salt
10.0/136 + 18x = 7.90/136
136 * 10 = 7.90 (136 + 18x)
1360 = 1074.4 + 142.2x
1360 - 1074.4 = 142.2x
285.6 = 142.2x
x = 285.6 / 142.2
x = 2
Hence the empirical formula of the compound is CaSO4. 2H2O
please someone describe the graph of the cooling curve of water !!!!!!!!!!!!!!!! Please answer !!!!!!!!!! HELP
It decreases it's temperature and it take about 10 hours for it to decrease
Yes buba booey
when an atom gains a valence electron, it become a (n)_____ion.
An atom that gains electrons and becomes negatively charged is known as an anion.
Hope it helps!
Based on the information in the table, which two elements are most likely in the same group, and why?
PLZ HELP ASAP What is the common name of this organism?
Answer:
Sea Anemone
Explanation:
17.5 kJ of energy is used to raise the temperature of 250 g of ethanol new temperature?
There becomes a relationship between all of the species in a community. This
relationship is called a
What is the temperature of 0.750 mol of a gas stored in a 6,850 mL cylinder at 2.21 atm? Use P V equals n R T. and R equals 0.0821 StartFraction L times atmospheres over moles time K EndFraction.. 2.95 K 5.24 K 138 K 246 K
Answer:
D on Edge2021
Explanation:
trust me bro
The temperature of 0.750 mol of a gas stored in a 6,850 mL cylinder at 2.21 atm will be 245.9K. Hence, Option (D) i.e, 246 K is correct. It can be solved with the help of Ideal gas equation.
What is Ideal gas equation ?
The ideal gas equation is formulated as: PV = nRT.
In the above equation, P refers to the pressure of the ideal gas, V is the volume of the ideal gas, n is the total amount of ideal gas that is measured in terms of moles, R is the universal gas constant, and T is the temperature.
Given ,
p = 2.21 atmV = 6850 ml (=6.85 L)n = 0.750 molR = 0.0821 atmL/mol KFrom,
PV=nRT
T = (2.21×6.85) ÷ (0.750×0.0821)
T = 245.9K i.e, 246 K approx
Therefore, The temperature of 0.750 mol of a gas stored in a 6,850 mL cylinder at 2.21 atm will be 245.9K. Hence, Option (D) i.e, 246 K is correct.
Learn more about Ideal gas here ,
https://brainly.com/question/8711877
#SPJ1
Correct answer gets brainliest
Answer:
e,b and d
Explanation:
Answer:
a,b,d,e
Explanation:
getting 20 characters longgggggggggbs o i can do thisssss
To protect against a fire, copper used for wiring in a house would best be covered with
Plastic or rubber as non metal are bad conductor of electricity.
PLEASE HELP THIS IS OVER DUE AND I NEED TO GET IT DONE IM REALLY BAD AT CHEMISTRY
In which state of matter (Solid, liquid, or a gas) do atoms/particles move the fastest?
Answer:
GasExplanation:
I hope it helps ❤❤❤.......
Answer:
Gas
Explanation:
Solid= Particles are really tight (Example: Ice Cube) Has a fixed shape
Liquid= Particles flow freely but is of constant volume.(Liquid fills it's container. Example: Water) No fixed shape
Gas= Particles move freely can fill its container has NO FIXED SHAPE or NO FIXED VOLUME(Example: Oxygen) Particels move FASTEST
Which of the following is true about alkaline earth metals? A. they have one valence electron B. they have two valence electrons C. they have three valence electrons D. they have four valence electrons
Answer:
they have two valence electrons
Explanation:
They readily give up their two valence electrons to achieve a full outer energy level, which is the most stable arrangement of electrons
If you may, I don't know how to graph. Thanks~
Answer: you should use the platform desmos to help you if you put in all the information it will give you the graph then you can just copy it on to your graph.
Explanation:
In which reaction is a small molecule formed from the atoms removed from a single reactant molecule?
Explanation:
During condensation reaction, two molecules combine to form a single molecule with the loss of a small molecule; in dehydration reaction, this lost molecule is water.
The reaction is a small molecule formed from the atoms removed from a single reactant molecule this reaction is knowing as condensation reaction.
How is the condensation process?Essentially, this is the reverse process of vaporization. In order for water vapor to undergo the process of condensation, which is the change from a gaseous state to a liquid state, it is necessary for a reduction in its temperature to occur until it reaches the dew point or an increase in the pressure to which it is subjected.
In this case the condensation reaction are when two molecules combine to form a single molecule with the loss of a small molecule, in dehydration reaction, this lost molecule is water.
See more about condensation at brainly.com/question/15563071
#SPJ2
2) How does matter change? That was a question students were
investigating in class. Each group had an experiment to carry out and
then determine if the changes observed indicated a physical or
chemical change. Here is one groups experimental procedure and
results.
Before
Mix
Aler
ALS
1000 m
vinegar
84
Rowe
1000 ml
solution
34
Rece
84
RP
23c
Changing
Tempe
Temper
Temperature
What type of change occurred? Cite any appropriate evidence.
A)
Chemical; the Alka-Seltzer tablet dissolved and
disappeared.
B)
Chemical; nothing new was formed.
C)
Chemical; a gas was produced and the temperature
changed.
D)
Physical; the Alka-Seltzer tablet dissolved and
disappeared.
13. When compared with the blood in the arteries,
the blood in the veins...
1 does not move at all
2 is under lower pressure
3 contains more gases
4 contains more water
Answer:
is under lower pressure
Explanation:
I think because arteries is for oxygenated blood so it flows very fast and the pressure is big but for veins , it is for deoxygenated blood that flows slower than oxygenated blood, so of course the pressure is lower.
Which of these elements has an atom with the most stable outer electron configuration?
1.Br 2.Ne 3.Zn 4.Ag
Answer:
Ne
Explanation:
Neon is the element with the most stable outer electron configuration because it has eight valence electrons that fill the outer shell. Eight electrons in the outer shell is the most stable arrangement of electrons. Neon is also a noble gas which means that due to it already having a complete outer shell, it doesn't lose, gain, or share electrons. Therefore, it is stable.
Hope that helps.
Determine the fraction of an original sample of tritium that remains unchanged after 24.62 years.
Answer: The answer is 1/4
Explanation:
Therefore, the fraction of an original sample of tritium that remains unchanged after 24.62 years will be 1/4.
What is fraction?
A fraction denotes a portion of something larger or, more broadly, any quantity of equal pieces.
Calculation of fraction
Given data:
t = 24.62 years = 25 years.
T = 12.5 years
Fraction can be calculated by using the formula:
N / [tex]N_{0}[/tex] = (1/2) power n..................(i)
n = t / T,......(ii)
Put the value of t and T in fraction equation.
n = 25 / 12.5
n = approx = 2.
Now, using equation (ii).
N / [tex]N_{0}[/tex] = (1/2) power 2
N / [tex]N_{0}[/tex] = 1/4.
Therefore, the fraction of an original sample of tritium that remains unchanged after 24.62 years will be 1/4.
To know more about fraction.
https://brainly.com/question/10354322.
#SPJ2
Which formula compares a sample of a gas under two different conditions of pressure and volume, if the temperature is constant?
⚪︎ x/y = k
⚪︎ xy = k
⚪︎ PV = k
⚪︎ V/T = k
⚪︎ P1V1 = P2V2
Answer:
Explanation:
V/t
Incomplete Lewis structures for the nitrous acid molecule, HNO2, and the nitrite ion, NO2-, are shown here. (a) Complete each Lewis structure by adding electron pairs as needed. (b) Is the formal charge on N the same or different in these two species? (c) Would either HNO2 or NO2- be expected to exhibit resonance?
The Lewis structure shows electron pairs in bonds between the atoms and the solitary electron pairs that remain for each atom. (a) in attached files, (b) the formal charge on N is the same +3, (c) NO₂⁻ exhibits resonance
-------------------------------
Nitrous acid molecule, HNO₂
Lewis structureN has 5 electrons
H has 1 electron
O has 6 electrons
There are two single bonds between H, O, and N
There is one double bond between N and the other O
Each bond represents two electrons
Excepting H, the other elements need to have eight electrons in total.
5 eletrons from N + 1 eletron from H + 12 electrons from the two O = 18 e⁻
18 e⁻ = 9 pairs or electrons
The two simple bonds + the double bond represent 4 electron pairs. So, there are still 5 electron pairs to place.
One of the O forms two single bonds, so it already has 2 pairs of electrons. It needs two more pairs to get the 8e⁻. So 4 electrons are placed arround this O.
The other O forms a double bond with N. The double bond represents 4 electrons. So this O needs another 4 electrons to get to the octet. Two pairs are placed arround this atom.
N forms a single bond with one O and a double bond with another O, so it already has 6 electrons. It only needs 2 more electrons to get to the octet. One pair is placed over the atom.
Finally H does not need to get any other electron
Nitrite ion, NO₂⁻
Lewis structureN has 5 electrons
O has 6 electrons
And there is a free negative charge, e⁻
There is one single bond between one of the O, and N
There is one double bond between N and the other O
The double bond is composed of a single bond and a resonant bond
Each bond represents two electrons
5 eletrons from N + 12 electrons from the two O + 1e⁻ = 18 e⁻
18 e⁻ = 9 pairs or electrons
The single bonds + the double bond represent 3 electron pairs. So, there are still 6 electron pairs to place.
One of the O forms one single bond, so it already has 2 electrons. It needs three more pairs to get the 8e⁻. So 6 electrons are placed arround this O.
The other O forms a double bond with N. The double bond represents 4 electrons. So this O needs another 4 electrons to get to the octet. Two pairs are placed arround this atom.
N forms a single bond with one O and a double bond with another O, so it already has 6 electrons. It only needs 2 more electrons to get to the octet. One pair is placed over the atom.
b) The formal charge on N (= +3) is the same for both species
The formal charges refer to the partial charges of each atom that are shared with another atom. It is the difference between the total valence electrons (8), the electrons that are not in the bond (2), and half the shared electrons (3).
formal charge on N = 8 - 2 - 3 = +3
c) Since nitrite ion, NO2- is the only one that exhibits a symetrical structure, it is the only one expected to show resonance.
------------------------------
You can learn more about the Lewis structure at
https://brainly.com/question/4144781
https://brainly.com/question/1968297
Question 17 of 25
What gets oxidized in an electrolytic cell made with nickel and copper
electrodes?
A. Ni2+
B. Ni(s)
C. Cu(s)
O D. Cu2+
Answer: it is Cu(s)
Explanation:
7. What is the molar concentration of glucose in a solution containing 4.82 g of
glucose in 29.5 mL of solution? Hint: This is a multi-step problem
If 16 moles of al react with 3 moles of S8 how many moles of Al2 S3 will be formed
Answer:
8 moles
Explanation:
Al reacts with [tex]S_8[/tex] to produce [tex]Al_2S_3[/tex] as
[tex]Al+S_8\rightarrow Al_2S_3[/tex]
The balanced chemical equation is
[tex]16Al+3S_8\rightarrow 8Al_2S_3[/tex]
In the reaction, 16 moles of [tex]Al[/tex] react with 3 moles of [tex]S_8[/tex] to produce 8 moles of [tex]Al_2S_3[/tex].
calculate the mass of atoms of carbon and 3 molecules of hydrogen
The mass of atoms of carbon and 3 molecules of hydrogen : 18 g/mol
Further explanationAn atomic mass unit ( amu or "u") is a relative atomic mass of 1/12 the mass of an atom of carbon-12.
The molar mass(molecular mass-formula mass-molecular weight(MW)) of a compound is the sum of the relative atomic mass (Ar) of the constituent elements of the compound
Can be formulated :
M AxBy = (x.Ar A + y. Ar B)
The mass of atom of Carbon(C)⇒Ar = 12 g/mol
The mass of 1 molecule of Hydrogen - H₂(MW) : 2 g/mol
The mass of 3 molecules of Hydrogen : 3 x 2 = 6 g/mol
So the mass of atoms of carbon and 3 molecules of hydrogen :
[tex]\tt 12+6=18~g/mol[/tex]
Factors that affects properties of a solution
3.Write the chemical equation for the reaction when methane burns in (2)
(a) Sufficient supply of oxygen
(b) Insufficient supply of oxygen
Answer:
a. CH4 + 2O2 = CO2 + 2H2O
b. 2CH4 + 3O2 = 2CO + 4H2O
An organism’s genotype is
A. its physical appearance.
B. its combination of alleles.
C. the mutations it inherits.
D. the crossing over that occurs during meiosis.
C- row 2, colun
II. Write "T" if the statement is true, and “F” if it is false,
Change the underlined word(s) to make the statement
true.
1. In the periodic table as suggested by Mendeleev, elements were
arranged in the order of increasing atomic number.
2. Sodium (Z=11) is a member of a group called alkaline earth
metals.
3. Elements to the extreme right of the periodic table are metals.
4. Metalloids have properties of metals and non-metals.
Answer:
1). In the periodic table as suggested by Mendeleev, elements were
the periodic table as suggested by Mendeleev, elements werearranged in the order of increasing atomic number.
--> T
2). Sodium (Z=11) is a member of a group called alkaline earth
Sodium (Z=11) is a member of a group called alkaline earthmetals.
--> T
3). Elements to the extreme right of the periodic table are metals.
--> F
They are non-metals .
4). Metalloids have properties of metals and non-metals.
--> T
What is happening to the energy storage molecules in the plants and humans in the space station?
Answer:
Answer is in photo
Explanation: