1: FALSE The physical properties of metals include shininess, malleability, ductility, and conductivity.
2: FALSE Neutrons are the particles in an atom that have a neutral charge. They aren't positive like protons. They aren't negative like electrons.
3: TRUE Dmitri Ivanovich Mendeleev was a Russian chemist and inventor. He is best remembered for formulating the Periodic Law and creating a farsighted version of the periodic table of elements. He is also known as the "father of the periodic table"
Answer:
1.T, 2.F., 3.T
Explanation:
2 is false because electrons have a negative charge neutrons have no charge
Question 2 of 25
Rain exists in which phase?
O A Liquid
O B. Solid
C. Plasma
D. Gas
Answer:
liquid
Explanation:
correct answer hope it helps
List 5 foods that contain bacteria?
How many grams of Ag2CO3 will precipitate when excess Na2CO3 solution is added to 40.0 mL of 0.679 M AgNO3 solution
Answer:
The answer is "[tex]37.45364 \ g[/tex]"
Explanation:
Equation:
[tex]2AgNO_3 (aq) + Na_2CO_3 (aq) \longrightarrow Ag_2CO_3 (s) + 2NaNO_3 (aq)[/tex]
Calculating the mol of [tex]AgNO_3[/tex]:
[tex]\to V = 40.0 mL\\\\[/tex]
[tex]= 40.0 \times 10^{-2} \ L \\\\[/tex]
[tex]\to n = Molarity \times Volume \\\\[/tex]
[tex]= 0.679 \times 40.0 \times 10^{-2}\\\\= 27.16 \times 10^{-2} \ mol[/tex]
mol of [tex]Ag_2CO_3= \frac{1}{2} \times n\\\\[/tex]
[tex]= \frac{1}{2} \times 27.16 \times 10^{-2}\\\\= 13.58 \times 10^{-2}\\\\[/tex]
Calculating the molar mass of [tex]Ag_2CO_3[/tex],:
[tex]= 2\times MM(Ag) + 1 \times MM(C) + 3 \times MM(O)\\\\= 2 \times 107.9 + 1 \times 12.01 + 3 \times 16.0\\\\= 275.81 \ \frac{g}{mol}[/tex]
Calculating the mass of [tex]Ag_2CO_3[/tex],
[tex]m = mol \times molar \ mass[/tex]
[tex]= 13.38 \times 10^{-2}\ mol \times 2.758 \times 10^2 \ \frac{g}{mol}\\\\= 37.45364 \ g[/tex]
TRUE OR FALSE? Alloys are used more than pure metals because they are generally softer and less likely to react with air or water.
Alloys are used much more than pure metals because they are generally stronger and less likely to react with air or water...
So I would say false
What is the specific rotation of a sample of carvone that is an equal mixture of the R and S enantiomers
Answer:
Zero
Explanation:
An an equal mixture of the R and S enantiomers of carvone is called a racemic mixture.
In a racemic mixture, the R enantiomer rotates plane polarized light in one direction while the S enantiomer rotates plane polarized light in another direction.
This cancels out the rotation due to each enantiomer since they are equal in magnitude but opposite in direction leading to a specific rotation of zero for the racemic mixture.
A 7.28 g sample of chromium metal was heated to produce chromium oxide. The weight of the compound was 10.63 g. What is the percent chromium in this compound?
Answer:
68.48%
Explanation:
The percent mass of an element in a compound tells us about the amount of such element contributed to the total compound.
In this case, 7.28 g sample of chromium metal was heated to produce chromium oxide with weight of 10.63 g. The percent mass of chromium in chromium oxide can be calculated by using the formula:
%mass of Cr = mass of Cr/mass of Chromium oxide × 100%
%mass of Cr = 7.28/10.63 × 100
%mass of Cr = 0.6848 × 100
%mass of Cr = 68.48%
What volume. In liters, of H2O(g) measured at STP is produced by the combustion of 15.63 g of natural gas (CH4) according to the following equation? CHale) +20269) CO2 + 2H2008)
Answer:
V = 43.95 L
Explanation:
Given data:
Mass of CH₄ decomposed = 15.63 g
Volume of H₂O produced at STP = ?
Solution:
Chemical equation:
CH₄ + 2O₂ → 2H₂O + CO₂
Number of moles of CH₄:
Number of moles = mass/molar mass
Number of moles = 15.63 g/ 16 g/mol
Number of moles = 0.98 mol
Now we will compare the moles of H₂O with CH₄.
CH₄ : H₂O
1 : 2
0.98 : 2×0.98 = 1.96 mol
Volume of hydrogen:
PV = nRT
1 atm × V = 1.96 mol × 0.0821 atm.L/mol.K × 273.15 K
V = 43.95atm.L / 1atm
V = 43.95 L
Trinitrotoluene (TNT, C7H5N3O6) undergoes complete combustion according to the following balanced chemical equation:
C7H5N3O6(s)+214O2(g)→7CO2(g)+32N2(g)+52H2O(l)
If 25.7 g of TNT is combusted in a 0.500 L container filled with O2 at a pressure of 7.02 bar and a temperature of 298 K, calculate the maximum mass of CO2 that could be produced.
Answer:
[tex]m_{CO2}=8.33gCO2[/tex]
Explanation:
Hello.
In this case, since the chemical reaction is:
[tex]C_7H_5N_3O_6(s)+\frac{21}{4} O2(g)\rightarrow 7CO_2(g)+\frac{3}{2} N_2(g)+\frac{5}{2} H_2O(l)[/tex]
Thus, since we have the initial moles of TNT:
[tex]n_{TNT}=25.7g*\frac{1mol}{227.13g} =0.113mol[/tex]
And the initial moles of oxygen given the ideal gas equation:
[tex]n_{O_2}=\frac{6.93atm*0.5L}{0.082\frac{atm*L}{mol*K}*298K}=0.142molO_2[/tex]
Given the 1:7 mole ratio between TNT and carbon dioxide and the 21/4:7 mole ratio between oxygen and carbon dioxide, we compute the yielded moles by each reactant:
[tex]n_{CO_2}^{by\ TNT}=0.113molTNT*\frac{7molCO_2}{1molTNT}=0.791molCO_2\\\\ n_{CO_2}^{by\ O_2}=0.142molO_2*\frac{7molCO_2}{21/4molO_2}=0.189molCO_2[/tex]
Thus, since oxygen yields less moles of carbon dioxide than TNT, we infer it is the limiting reactant, therefore, the produced mass of carbon dioxide is:
[tex]m_{CO2}=0.189molCO2*\frac{44.01gCO2}{1molCO2}\\\\m_{CO2}=8.33gCO2[/tex]
Best regards!
An excess of oxygen reacts with 451.4 g of lead, forming 374.7 g of lead(II) oxide. Calculate the percent yield of the reaction.
Answer: The percent yield of the reaction is 77.0 %
Explanation:
[tex]2Pb+O_2\rightarrow 2PbO[/tex]
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
[tex]\text{Number of moles of lead}=\frac{451.4g}{207.2g/mol}=2.18moles[/tex]
[tex]\text{Number of moles of lead oxide}=\frac{374.7g}{223.2g/mol}=1.68moles[/tex]
According to stoichiometry:
2 moles of [tex]Pb[/tex] produces = 2 moles of [tex]PbO_2[/tex]
2.18 moles of [tex]Pb[/tex] is produced by=[tex]\frac{2}{2}\times 2.18=2.18moles[/tex] of [tex]PbO_2[/tex]
Mass of [tex]PbO_2[/tex] =[tex]moles\times {\text {Molar mass}}=2.18\times 223.2g/mol=486.6[/tex]
percent yield =[tex]\frac{374.7g}{486.6g}\times 100=77.0\%[/tex]
Why do gases diffuse more quickly than liquids?
Choose the correct answer.
A) Liquids can be compressed easily.
B)The particles in gases are not mobile.
C)Liquids are always at lower temperatures than gases.
D)Gas particles move rapidly and have space between them.
Answer:
D)Gas particles move rapidly and have space between them.
Explanation:
Matter exists in three states namely: solids, liquids and gases. The particles contained in these three states are different from one another. In the gaseous state, the particles are FAR APART from one another i.e. space exists and they move at a very fast rate in contrast to the particles of a liquid, which have less space and move slower.
This rapid movement of gas particles within a less restricted space accounts for the reason why gaseous substances DIFFUSE more quickly than liquids.
What is one example of chemical weathering affecting a rock
Answer:
one example of chemical weathering is when carbon dioxide mixes with water.
Explanation:
when dioxide mixes with water it creates carbonation.
The three lines in this Lewis dot structure represent the.
A)
three valence electrons of dinitrous oxide.
B)
six electrons in the triple bond of diatomic nitrogen.
C)
three electrons joining two nitrogen atoms in a diatomic molecule.
D)
three double bonds between the valence electrons of diatomic nitrogen.
Answer:
B) . six electrons in the triple bond of diatomic nitrogen
Explanation:
The three line in this Lewis dot structure represents the six electrons in the triple bond of diatomic nitrogen.
Nitrogen is made up of 7 electrons with 5 valence ones.
A lewis structure is made up of the symbol of the element surrounded by dot to represent the valence electrons.
In this nitrogen molecule, both species share 6 electrons. This makes each nitrogen atom isoelectronic with neon.
Answer them please thanks
Answer:
(3) sorry if I'm wrong
7. (1-fertilization [sorry if wrong again]
8. (4-mitosis
Explanation:
I'm learning about this right now...Sorry if I'm wrong but I'm pretty sure they're right! Hope this helps tho! if I'm right maybe mark me brainliest?
PLEASE HELP IM TIMED
Which of the following is not an oxidation-reduction reaction?
Upper X e upper F subscript 6 (s) right arrow upper X e upper F subscript 4 (s) plus upper F subscript 2 (g).
2 upper C s (s) plus upper I subscript 2 (g) right arrow 2 upper C s upper I (s).
2 upper H subscript 2 upper S upper O subscript 4 (a q) plus 2 upper B a (upper O upper H) subscript 2 (a q) right arrow 2 upper B a upper S upper O subscript 4 upper H subscript 2 upper O (l).
Upper Z n (s) lus 2 upper A g upper N upper O subscript 3 (a q) right arrow upper Z n (upper N upper O subscript 3) subscript 2 (a q) plus upper A g (s).
Answer: choice 2
Explanation:
PLEASE HELP!! Circuit A consist of two wires and a battery. Circuit B consist of the same strength battery and the same type of wires, but it also contains a light bulb. Which circuit has more resistance?
Answer:
light bulb B
Explanation:
more resistance
which stimulate causes high energy emotional elation dehydration and damage serotonin producing neurons
Answer:
ecstasy
Explanation:
The atomic masses of 20Ne (90.48 percent), 21Ne (0.27 percent), and 22Ne (9.25 percent) are 19.9924356, 20.9938428, and 21.9913831 amu, respectively. Calculate the average atomic mass of neon. The percentages in parentheses denote the relative abundance
Answer:
20.180042 amu
Explanation:
From the question given above, the following data were obtained:
Isotope A (20Ne)
Mass of A = 19.9924356 amu
Abundance (A%) = 90.48%
Isotope B (21Ne):
Mass of B = 20.9938428 amu
Abundance (B%) = 0.27%
Isotope C (22Ne):
Mass of C = 21.9913831 amu
Abundance (C%) = 9.25%
Average atomic mass of Neon =.?
The average atomic mass of Neon can be obtained as follow:
Average atomic mass = [(mass of A × A%)/100] + [(mass of B × B%)/100] + [(mass of C × C%)/100]
= [(19.9924356 × 90.48)/100] + [(20.9938428 × 0.27) /100] + [(21.9913831 × 9.25) /100]
= 18.0891557 + 0.05668338 + 2.03420294
= 20.180042 amu
Therefore, the average atomic mass of Neon is 20.180042 amu
Which of the following macromolecule is the main energy source for most living organisms?
A. Nucleic Acids
B. Carbohydrates
C. Lipids
D. Proteins
Answer:
Carbohydrates
Explanation:
Living things use carbohydrates as their main source of energy. The breakdown of sugars, such as glucose, supplies immediate energy for cell activities. Plants, some animals, and other organisms also use carbohydrates for structural purposes.
Draw and name the structures of the carboxylic acids and esters you put together using molecular models.
Answer:
This question is incomplete
Explanation:
However, when the carboxylic acids and esters put together are obtained, the procedure below can be followed in drawing and naming them.
For carboxylic acid,
1) it should be noted that the functional group here is -COOH which is drawn as -C = OH
|
OH
2) The carbon of the functional group is included among the carbon to be counted when naming the structure. For example, the compound below is propanoic acid.
CH₃CH₂COOH - As you can see that there are 3 carbons linked chain there.
3) As can be seen in (2) above, the suffix "oic" is used to name carboxylic acids
4) The carbon chain here is saturated (meaning there is no double or triple bond within the carbon chain)
Example of a structure of carboxylic acid is
H₃C - CH₂ - CH₂ - C = OH
|
OH
The structure above is a butanoic acid
For ester
1)The functional group here is -COO- . which can be drawn as
- C = O
|
O -
(meaning one oxygen atom is double bonded to the carbon and the other oxygen atom is bonded to another carbon chain)
2) The alkyl group attached to the oxygen atom is first of all mentioned before the carbon chain attached from the left is mentioned. For example, CH₃CH₂CH₂COOCH₂CH₃ is ethyl butanoate
3) As seen from (2) above, the suffix "oate" is used to end the name of esters
4) As also seen from (2) above, the carbon of the functional group is also included while counting the carbon chain of the parent name (butanoate).
5) The carbon chains here are also saturated.
Example of this ester is
CH₃CH₂C = O
|
O - CH₂CH₃
The name of this compound is ethyl propanoate
A. filtration B. sieving C. using a magnet D. decantation
E. evaporation
Directions: Choose the best technique that can be used to separate the substances or
materials in each mixture. Write the letter of your answer on the space before the nu
1. Cornstarch and water
2. Iron and sulfur
3. Rice grains and stones
4. Pebbles and soil
5. Muddy water
6. Ground pepper and water
7. Flour and coarsely ground corn
8. Needles in a box of beads
9. Sesame seeds in soy sauce
10. Pebbles and iron nails
11. Fine sand from rocks
12. Sand from water
13. Gravel and sand
14. Salt and iron filings
15. Pins from assorted buttons
16. Coconut oil from coconut milk
17. Sand and pebbles
18. Pasta from water
19. Sand and thumb tacks
20. Salt solution
Answer:
Explanation:
1. Cornstarch and water - decantation
2. Iron and sulfur
3. Rice grains and stones - sieving
4. Pebbles and soil - decantation
5. Muddy water - decantation
6. Ground pepper and water - decantation
7. Flour and coarsely ground corn - sieving
8. Needles in a box of beads - using a magnet
9. Sesame seeds in soy sauce -
10. Pebbles and iron nails - using a magnet
11. Fine sand from rocks - sieving
12. Sand from water - filtration
13. Gravel and sand - sieving
14. Salt and iron filings - sieving
15. Pins from assorted buttons - using a magnet
16. Coconut oil from coconut milk - filtration
17. Sand and pebbles - sieving
18. Pasta from water - sieving
19. Sand and thumb tacks - using a magnet
20. Salt solution - filtration
A scientist is considering formaldehyde (HCHO) for use in an experiment. She is studying the strength of triple bonds in molecules. Is
ormaldehyde a good choice for her to use? Why?
A. Yes, HCHO has three triple bonds.
B. Yes, HCHO has one triple bond.
C. No, HCHO has a double bond but no triple bonds.
D. No, HCHO has only single bonds.
PLEASE HELP ME!!!!!!!!!!!!!!!!!!!
WRITE A SHORT PASSAGE ON HOW FIBRES ARE SPUN
HELPPP WILL MARK AS BRAINLIEST
Answer: Spun yarn is made by twisting staple fibers together
To make a cohesive thread Or “single”. Twisting fibers, into yarn in the process called spinning can be dated back to the upper Paleolithic. Yarn spinning was one of the first processes to be industrialized.
Explanation:
1 point
Which element requires the least amount of energy to remove its valence electron(s)?
barium
chlorine
oxygen
carbon
When a material gains thermal energy and melts, it is undergoing a physical change.
Answer:
True, it undergoes a physical change.
Explanation:
A physical change is a change that does not change the chemical makeup of a material. This includes altering its shape.
formal charge of hcooh
Answer:
What is the question?
A beverage manufacturer wants to increase The solunility of carbon dioxide in its carbonated drinks as beverages produced which action will increase the solubility of CO2 gas the most
A. Decreasing the pressure on it
B. Increasing stirring
C. Decreasing its temperature
D. Increasing its temperature
Answer: C
Explanation:
what elements make up duralumin( an alloy)?
Answer:
In addition to aluminium, the main materials in duralumin are copper, manganese and magnesium.
Answer:
The original composition has been varied for particular applications; it may contain about 4 percent copper, 0.5–1 percent manganese, 0.5–1.5 percent magnesium, and, in some formulations, some silicon.
What type of bond would be expected between Mg and Ti?
A.hydrogen bond
Bionic bond
C.covalent bond
D.metallic bond
What is the best-known feature of sedimentary
rocks?
A. ripple marks
B. fossils
C. graded bedding
D. cross-bedding
Answer:
option is (b)
Explanation:
please mark me as brilliant
25. Which of the following statements concerning atomic structure is/are correct?
1. The nucleus contains most of an atom's mass.
2. The nucleus contains all the positive charge of an atom.
3. Electrons surround the nucleus and account for the majority of an atom's volume.
1 only
2 only
3 only
2 and 3
1, 2, and 3
Answer:
It would be 2 and 3
The image shows the structure of an atom, I hope it helps :)
To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Therefore, the correct option is option 2,3.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron. The nucleus contains all the positive charge of an atom. Electrons surround the nucleus and account for the majority of an atom's volume.
Therefore, the correct option is option 2,3.
To know more about atom, here:
https://brainly.com/question/13518322
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