Answer:
The first step in the Scientific Method is to make objective observations. These observations are based on specific events that have already happened and can be verified by others as true or false. Step 2. Form a hypothesis.
Answer:
False
Explanation:
The first step of the scientific method is to make an observation.
which of the following statements is true about alkali?
A) bases that soluble in water
B) shows a pH value less than 7
C) Ionises in water to form hydroxonium ions
D) Reacts with carbonate salt to release carbon dioxide gas
Answer:
it should be letter c
Explanation:
I hope this help
If the hydrogen ion concentration, (H+), in a solution is 5.39 x 10-8 M,
what is [OH-]?
A.1.86 x 1021 M
B. 1.86 x 10-7 M
Answer: 1.86*10^-7M
Explanation:
Answer:
B. 1.86 x 10^-7 M
Explanation:
Unknown # 41
Flame Test Color: Lilac
Addition of HCl(aq): NR (No reaction)
Addition of HCl(aq) and BaCl2(aq): NR (No reaction)
Addition of HNO3(aq) and AgNO3(aq): Yellow precipitate
What is the unknown ionic compound molecular formula?
What is the molarity of 2 moles of a compound dissolved in 4 L of water?
A. 2 M
B. 0.5 M
C. 4M
D. 1 M
Answer:
[tex]\boxed {\boxed {\sf B. \ 0.5 \ M}}[/tex]
Explanation:
Molarity is a measure of concentration in moles per liter. The formula for calculating molarity is:
[tex]molarity= \frac{moles \ of \ solute}{ liters \ of \ solution}[/tex]
There are 2 moles of a compound or the solute. There are 4 liters of water or the solution.
moles of solute= 2 mol liters of solution = 4 LSubstitute the values into the formula.
[tex]molarity = \frac{ 2 \ mol}{ 4 \ L}[/tex]
Divide.
[tex]molarity= 0.5 \ mol /L[/tex]
1 mole per liter is equal to 1 Molar, so the solution's molarity of 0.5 mol/L is equal to 0.5 M.
[tex]molarity = 0.5 \ M[/tex]
The molarity of the solution is 0.5 Molar and choice B is correct.
What is the concentration of a solution formed by diluting 25.0 ml of a 3.8M glucose solution to 250ml
Explanation : số mol glucose 3.8M là :
n = Cm . V = 3.8 . 25 =95
=> Cm khi pha loãng = [tex]\frac{n}{V}[/tex] = [tex]\frac{95}{250}[/tex] = 0.38M
According to molar concentration, the concentration of a solution formed by diluting 25.0 ml of a 3.8 M glucose solution to 250 ml is 0.38 M.
What is molar concentration?Molar concentration is defined as a measure by which concentration of chemical substances present in a solution are determined. It is defined in particular reference to solute concentration in a solution . Most commonly used unit for molar concentration is moles/liter.
The molar concentration depends on change in volume of the solution which is mainly due to thermal expansion. Molar concentration is calculated by the formula, molar concentration=mass/ molar mass ×1/volume of solution in liters.
In terms of moles, it's formula is given as molar concentration= number of moles /volume of solution in liters.In case of 2 solutions given it is calculated as M₁V₁=M₂V₂,on substitution, M₂=3.8×25/250=0.38 M.
Thus, the concentration of a solution formed by diluting 25.0 ml of a 3.8 M glucose solution to 250 ml is 0.38 M.
Learn more about molar concentration,here:
https://brainly.com/question/21841645
#SPJ5
Susan said, "if I fertilize my geranium plants, they will blossom"
Choose the correct step in the scientific method
A. recognize a problem
B. from hypothesis
C. test the hypothesis with an experiment
D. draw conclusions
Answer:
This is called a hypothesis, which can be identified by the if... then... format.
So, the correct option is B. Form a hypothesis.
Let me know if this helps!
Answer:
C
Explanation:
1. In regards to curly hair, which of the following statements
are TRUE? (select 2 answer choices).
A. Curly hair develops over time. It is not acquired at birth.
B. Curly hair can lead to harmful mutations in the body.
C. Curly hair results from a change in the gene that
codes for hair structure.
D. People with curly hair have different hair protein structures than people with
straight hair.
Answer here:
Answer:
A and D are the answers
Explanation:
the other two don't make sense
The statements C and D are correct, i.e., curly hair have different protein structure from straight hair and curly hair results from a change in the gene.
What is protein?Proteins are biomolecules made of amino acids. Proteins are very essential to all living things and contributes the body structure. Proteins are mainly up taken through diet and they are the main source of energy.
Hair is made of keratin protein. Keratin makes up our skin and nails too.Curly hair is originating by birth not developing over time. Curly hair is more likely to be occurring through inheritance.
The protein structure the hair follicle is some more bend for curly hair. Curly hair and straight hair originates from different gene traits. The gene type is inherited from the parents.
Hence, for people with curly hair have different protein structure and it result from a change in gene that code for hair structure. Thus options C and D are correct.
To learn more about proteins, refer the link below:
https://brainly.com/question/2193769
#SPJ2
What happens when The vapour obtained by dropping conc. H2SO4 in a mixture of KI and MnO2 is treated with hypo solution
The reaction between H2SO4 in a mixture of KI and MnO2 yields iodine which reacts with hypo solution by titration and the iodine is decolorized.
Iodine is decolorized.
The first reaction stated in the question occurs as follows;
2 KI (aq) + 2 H2SO4 (aq) + MnO2 (s) → MnSO4 (aq) + K2SO4 (aq) + I2 (s) + 2 H2O (l)
The reaction here is the formation of iodine from MnO2 and KI in the presence of dropwise H2SO4.
Hypo is the common name of sodium thio-sulphate or sodium hypo-sulfite.
The equation of the titration reaction is;
2Na2S2O3 + I2→ Na2S4O6 + 2NaI
When this reaction takes place, iodine is decolorized due to its reduction to I^-.
For more information see https://brainly.com/question/16857360
All three states of matter can be ____________ or a solvent in a solution.
in order to decrease the freezing point of 500. g of water to 1.00° c how many grams of ethylene glycol (C2H602)must be added (KF=1.86°C kg solvent)
Answer:
if wrong sorry ok????
Calculate the amount of mole(s) of CoF2 required to react with 12.8 moles of HCI.
CoCl2 + 2HF --> CoF2 + 2HCI
Explanation:
here's the answer to your question
What does the prefix trans-indicate?
A. There are at least two double bonds in the molecule.
B. The carbons on either side of the double bond are pointed in
opposite directions.
C. The molecule is an alkane with no double bonds.
O D. The carbons on either side of the double bond are pointed in the
same direction
Answer:
B. The carbons on either side of the double bond are Pointed in opposite directions
Ting tong !!!!
Surprised!!!!!!!
Can you solve this question genius.
I need the answer.
Also I Have advantage for you if you help me on this question.
if you answer all questions with correct I will follow you! Marks as branlist!
Bye bye!!!!!!!! Answer it ok!!!
I have waste 50 pts on this. if you give me answer of other questions on this for pts I will report your answer
if you give me all answer of this I will make you brainlist.!!!!!!!
how can we separate the sugar from sugar solution
What is Spontaneous ion
WM "Please write the molecular formula for the following by criss cross method. 1. Calcium nitrate 2. Sodium bicarbonate 3. Magnesium nitrite 4. Sodium chloride 5. Hydrogen sulphate 6. Hydrogen chloride T-Aluminium bisulphate 8 Aluminium chloride 9. Aluminium sulphate 10. Hydrogen Nitrate
Answer:
1 Ca(NO3)2
Calcium- Ca, Valency 2
Nitrate- NO3, Valency 1
AFTER CRISS CROSS:
Ca1(NO3)2
Ca(NO3)2
2 sodium bicarbonate = NaHCO3
Na = Sodium = (Na)+
HCO3 = bicarbonate = (HCO3) -
Na HCO3
3 magnesium nitrite
+2 _ 1
Mg2(NO3)2
4 Na Cl
+1 _1
formula NaCl
5 hydrogen sulphide
H SO4
+1 _2
formula H2SO4
6 H Cl
+1 _1
HCl
7 AL2 HSO4
+2 -2
AL2(HSO4)3
8 NH4 Cl
+1 _1
NH4Cl
9 NH4 SO4
+1 _2
(NH3)2SO4
10 H NO3
+1 _1
HNO3
Plzzz help do your best to answer these questions
The empirical formula is the simplest formula of a chemical compound.
To find the empirical formula, we take the following steps;
Divide the percentage by mass of each element by its relative atomic mass.Divide the quotient of each by the lowest value obtained instep 1 aboveWrite the result of step 2 above as the subscript following each atom.1) O - 88.10/16, H - 11.190/1
O - 5.5, H - 11.19
O - 5.5/5.5, H - 11.19/5.5
O - 1, H - 2
Empirical formula = OH2
2) C - 41.368/12 H - 8.101/1, N - 32.162/14, O - 18.369/16
C - 3, H - 8, N - 2, O - 1
C - 3/1, H - 8/1 N - 2/1 O - 1/1
C - 3, H - 8, N - 2, O - 1
Empirical formula = C3H8N2O
To obtain the molecular formula where n = number of atoms of each element;
Molecular weight = 174.204 g/mol
[ 3(12) + 8(1) + 2(14) + 16]n = 174
n= 174/88
n = 2 (to the nearest whole number)
Hence, we have;
[C3H8N2O]2
The molecular formula is C6H16N4O2
3) C - 19.999/12, H - 6.713/1, N - 46.646/14, O - 26.641/16
C - 2, H - 7, N - 3, O - 2
C - 2/2, H - 7/2, N - 3/2, O - 2/2
C - 1, H - 4, N - 2, O - 1
Empirical formula - CH4N2O
https://brainly.com/question/1363167
Answer: Freezing point depression
Explanation:
freezing point depression is a phenomenon that describes why adding a solute or solvent results in the lowering of the freezing point of the solvent
What are isotopes_???
Answer:
Below!
Explanation:
Isotopes are elements with a similar chemical makeup and the same atomic number, but a different atomic mass and number of neutrons . An example of this would be carbon-12, carbon-13, and carbon-14. Three isotopes of the element carbon that have the same 6 protons but have a different neutron count. A simple way to explain isotopes would be to say that they are just different "versions" of an element.
Hope this helps ya! Best of luck <3
Environmental scientists are unconcerned with methods to preserve natural resources.
Please select the best answer from the choices provided
T
F
Answer:
False
Explanation:
are standard electrode potential and standard hydrogen potential same?
Answer:
Potentials of any other electrodes are compared with that of the standard hydrogen electrode at the same temperature. Hydrogen electrode is based on the redox half cell: 2 H+(aq) + 2 e− → H2(g)..
what is the formula of water
Answer:
The formula of water is H20
why water can reduce unpleasant smell that produce from methane gas ?
Answer:Water contains Oxygen the purified the methane gas
Explanation:
Using your answers from part C, complete the chemical formula of each compound. If the number of ions is 1, leave that
number out of the formula.
Drag each number to the correct location. Numbers may be used more than once
Answer:
1;1, 2;1, 3;1, 1;2, 1;1, 3;2, 1;3, 2;3, 1;1.
I hope this will help.
Answer:
This is what the answer looks like
Explanation:
Which of the following is the correct Lewis structure for methane (CHA)?
O A. H-C-H
H
I-0-I
OB. H-H-C-H-H
0
H
O c. H:C:H
H
OD H-C-H
The correct lewis structure of methane(CH4)
C. H:C:H:H
career in chemistry list ten
Explanation:
Chemistry Teacher.
Chemical Engineer.
Forensic Scientist.
Geochemist.
Biochemists
Pharmacologist
Analytical Chemist
Envionmental chemist
Water Chemist
Catalysis
Question 5: thanks you
Answer:
A linear molecule has a bond angle of 180°
2500m into kilometer
1 meter = 1000 km
2500 meter = 2500/1000 km
= 2.5 km
what is meant by reaction element
Answer: A reaction element are those elements that can take part in a chemical reaction.
Explanation:
An element is made up of atoms that has the same atomic number. It is the basic material of which all matter is composed of. These elements cannot be broken down further into smaller substances by any chemical reaction. Each element has a unique number of protons in its atom. For example,
--> a hydrogen atom has 1 proton,
--> a Helium atom has 2 protons,
--> a Lithium atom has 3 protons, and
--> a carbon atom has 6 protons.
A chemical reaction on the other hand involves rearrangement of the constituent atoms of reactants to create different substances as products. The bonds between atoms are either broken or created to form new molecules. There are different types of chemical reaction which includes:
--> Decomposition reaction
--> Neutralization reaction
--> single displacement reaction and
--> combustion reaction.
1 atm is equal to
O 1 mmHg
• 14.7 mmHg
• 76 mmHg
© 760 mmHg
Answer:
C 760 mm of hg
because this is the atmospheric pressure at sea level
