Answer:
xhhhvxhxgjhgogftsvicsdgfsytdhdrrygyfhd
Explanation:
ywwgzwu9wu9wsussg the the
Short Answer Questions 18 points
1) What year was Mendeleev born? _______________________________________
2) Where was Mendeleev born? ______________________________________
3) Explain how Mendeleev arranged his periodic table.______________________________________
4) What were the 3 Elements that were missing from Mendeleev’s Periodic Table?
__________________________________________________________________
5) When did Mendeleev die? Exact date ____________________________________
6)Which particles are in the nucleus of an atom? ______________________________
1) He was born on February 8, 1834
2) He was born in Tobolsk, Russia
3) Mendeleev arranged the elements in order of increasing relative atomic mass.
4) Gallium, germanium, and scandium
5) He died on February 2, 1907
6) Protons (positive charge) and neutrons (neutral charge)
1. A student is titrating 0.61 M KOH with 14.5 mL of 0.47 M H2SO4
ii. What volume of 0.61 M KOH is needed to titrate the H2SO4?
ii. What mass of water can be produced if 131 g of the H2SO4 solution react with 225 mL
of 0.61 M KOH?
Can someone help me with this?
Answer:
M KOH = 0.61 M
V H2SO4 = 14.5 ml
M H2SO4 = 0.47 M
Volume KOH = ?
( V . M . valensi) KOH = (V . M . valensi) H2SO4
V . 0.61 . 1 = 0.47 . 14.5 . 2
V KOH = (0.47 . 14.5 . 2) / 0.61
V KOH = 22.34 ml
see more the answer at the pic
Which of the following pairs of elements is least likely to combine to form a compound?
A. Aluminum AI and phosphorus P
B. boron B and neon S
C. carbon C and sulfur S
D. oxygen and fluorine F
Answer:
c.carbon C and sulfur S
Explanation:
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.
List 5 foods that contain bacteria?
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]
Which material is found in asteroids?
Answer:
Asteroids are made of rock, metals, and other elements. Some even contain water. Asteroids that are mostly stone sometimes are more likely to lose piles of rubble. Asteroids that are mostly iron are more rock-solid.
Explanation:
Answer:
asteriods are made of rocks. asteroids that are mostly iron are more, well, rock-solid
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 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.
Calculate the pH in the titration of 25.0 mL of 0.100 M acetic acid by sodium hydroxide after the addition to the acid solution of 10.0 mL of 0.100 M NaOH. (Ka for acetic acid is 1.8x10-5.)A.8.72B. 12.22C. 7.14D. 4.57
Answer:
see the pic for more detail
The pH of the solution after the titration has been 1.318.
pH can be defined as the negative logarithmic values of the hydrogen ion concentration in the solution.
The remaining acid solution has been responsible for the pH of the solution.
The moles of acid can be given by:
Moles = Molarity × Volume
Moles of acetic acid = 0.1 M × 0.025 L
Moles of acetic acid = 0.0025 moles
Moles of NaOH = 0.1 M × 0.01 L
Moles of NaOH = 0.001 moles.
By the neutralization reaction, the moles of acid remaining has been:
Mole of acid remaining = Moles of acid - Moles of NaOH
Moles of acid remaining = 0.0025 - 0.001
Moles of acid remaining = 0.0015 moles.
The hydrogen ions liberated by the acetic acid have been equivalent to the moles of acetic acid.
Thus, the moles of hydrogen ions = 0.0015 mol.
The concentration of hydrogen ions has been:
Molarity = [tex]\rm \dfrac{moles}{volume\;(L)}[/tex]
Molarity of hydrogen ion = [tex]\rm \dfrac{0.0015}{0.025\;+\;0.01\lL}[/tex]
Molarity of the hydrogen ion has been = 0.0428 M.
The pH of the solution has been:
pH = -log [Hydrogen concentration]
pH = -log (0.0428)
pH = 1.318.
The pH of the solution after the titration has been 1.318.
For more information about the pH of titration, refer to the link:
https://brainly.com/question/9707819
What happens in a chemical reaction?
a. Atoms are destroyed.
b. Atoms are created.
c. Molecules are created.
d. Atoms are rearranged.
Please select the best answer from the choices provided
A
B
С
D
Pls help please :((
Answer:
During the reaction, chemical bonds break in the reactants and new chemical bonds form in the products.
Answer:
d. Atoms are rearranged.
Explanation:
PLEASE HELP!! I WILL MARK THE 1st ONE BRAINLIEST!
Answer:
I hope you do well on the test good luck
Explanation:
How does Newton’s second law apply to the golf tee balanced on the hoop? How does Newton’s second law apply to the golf tee when the hoop is pulled away?
please answer asap
There are total three laws of newtons, first law of newtons, second law of newton and third law of newton. Therefore, when a golf club is subjected to an imbalanced force, its velocity changes, which is according to newton’s second law.
What is newton's second law?According to Newton's Second Law of Motion, acceleration (gaining speed) occurs when a force acts on a mass (object). Riding a bicycle is a great example of this rule of motion in action. The mass is represented by your bicycle. The force is generated by your leg muscles pulling on the pedals of your bicycle.
The ball remains balanced on the tee due to the balanced forces of gravity downhill and upward. Force equals mass multiplied by acceleration (f=ma). When a golf club is subjected to an imbalanced force, its velocity changes.
Therefore, when a golf club is subjected to an imbalanced force, its velocity changes, which is according to newton’s second law.
To know more about newton's second law, here:
https://brainly.com/question/13447525
#SPJ2
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
Which of the following conclusions about the two intermolecular forces is correct? X represents London dispersion forces, and Y represents ion-dipole forces. X represents dipole-dipole forces, and Y represents ion-dipole forces. X represents hydrogen bonding, and Y represents dipole-dipole forces. X represents London dispersion forces, and Y represents dipole-dipole forces.
Answer:
X represents London dispersion forces, and Y represents dipole-dipole forces.
Explanation:
What is the velocity if you travel 60 m to the right in 20 seconds
Answer:
The velocity would be if m was meters +1200
Explanation:
im smart
PLEAE HELP ASAP WILL MARK BRAINLYLIST! Question 2 the answers are under 2
Answer:
Alkali Metals
Explanation:
They're the most reactive elements in group one.
How does the VSEPR theory explain molecular shape?
A. Valence electrons modify core electron orbitals.
B. Intermolecular forces distort electron bonds.
C. Electron pair attractions pull atoms together.
D. Electron pairs repelling each other push atoms apart.
Answer:
D. Electron pairs repelling each other push atoms apart
Explanation:
Hope this helps :) I just got it wrong on ap3x so I'm sure this is right
The VSEPR theory explain molecular shape by stating that the Electron pairs repelling each other push atoms apart. Hence, Option (D) is correct
What is VSEPR theory ?
Valence shell electron pair repulsion (VSEPR) theory, is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms.
It is also named the Gillespie-Nyholm theory after its two main developers, Ronald Gillespie and Ronald Nyholm.
Therefore, The VSEPR theory explain molecular shape by stating that the Electron pairs repelling each other push atoms apart. Hence, Option (D) is correct.
Learn more about VSEPR theory here ;
https://brainly.com/question/2293021
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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?
A chemical equation is shown:
Al + O2 A1203
According to the law of conservation of mass, how many atoms of oxygen exist in the products of this reaction?
6
5
3
2
Answer:
Well the answer of 1 and 3 is WRONG based on the 1 star review and the answer of 3 is wrong too I just took a test with this question.
Explanation:
Sorry...
Answer:
it's 6
Explanation:
I just took the test and got it right
Please help thankyou
Hope this serves helpful to u!!
Hope this helps by the way as well
Good luck!!!
what's the molar mass of alumina, AI2O3? the atomic weight of alumina is 26.98 and the atomic weight of oxygen is 16.00
Answer:
the answer is 101.96 g/mo
Explanation:
Answer:
101.96f/mal
Explanation:
5. What must happen for a seed to emerge from the soil as a seedling?
Answer:
It must have sunlight and water and neutrants and be fertilized
Explanation:
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]
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
Oil is removed from the refrigerator vapor by a:
A compressor, condenser, and a evaporator
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
What is the orbital notation for Al+3?
O 1s2 2s22p6
O 182 2s2 2p6 352 3p1
O 1s2 2s2 2p6 352 3p5
O 1s2 2s22p6 352 3p6
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!