Answer:
the family have been served dinner with the kids
the house has been watched by the police for week
the lights went off when i was doing my home work
1. What kinds of metals are REALLY reactive? why?
2. What kinds of non-metals are REALLY reactive? why?
3. What group on the periodic table doesn’t react at all? why?
Answer:
1. Alkali metals (group 1)
2. halogens (Group 17)
3. noble gasses (group 18)
Explanation:
1. alkali metals only have one valence electron meaning that they really want to lose that one valence electron to get a full octet.
2. halogens have 7 valence electrons meaning that they just need to gain 1 to get a full octet.
3. Nobel gasses already have a full octet meaning that they don't want to react. (atoms only react to get a full octet)
I hope this helps. Let me know if anything is unclear.
The enthalpy of combustion of gasoline (C8H18) is 5471 kJ mol-1. How much heat will be produced by burning 1 gallon of gasoline at 25°C? (Density of gasoline = 0.703 g/mL; 1gallon = 3.78 L) Show your work clearly.
Answer:
127529 KJ
Explanation:
Since 1gallon = 3.78 L= 3780 ml
The density of C8H18= 0.703 g/mL
Density = mass/volume
Mass= Density × volume
Mass= 0.703 g/mL × 3780 ml
Mass= 2657.34 g
Molar mass of C8H18= 114 g/mol
Number of moles= mass/molar mass
Number of moles= 2657.34/114
Number of moles= 23.31 moles
Since 1 mole evolved=5471 kJ
23.31 moles = 5471 kJ × 23.31 = 127529 KJ
A teacher asks students to describe the physical properties of 10 mL of vinegar and 10 mL of milk. When the students finish listing the physical properties in their science notebooks, the teacher pours the vinegar and milk into the same beaker. The students are surprised to see a white solid substance form within the beaker as the two substances are combined.
What occurs within the beaker as the teacher mixes the vinegar and milk?
1. A chemical change that produces a precipitate
2. A physical change that creates a new substance
3. A physical change that produces a precipitate
4. A chemical change that produces no new substances
Answer:
1. A chemical change that produces a precipitate
Explanation:
A solid substance that is formed from a liquid phase is called a precipitate.
A reaction that produces a precipitate is called a precipitation reaction.
Precipitation reactions are an example of a chemical change.
Thus the correct answer is option 1: A precipitate was formed when vinegar and milk were mixed (as there were no solid substances when they were apart).
11. Chemist Ernest Rutherford performed the gold foil experiment in which he concluded the
atom is mostly empty space, with a small, dense, positively charged center. Rutherford's
discovery of the proton did not fully account for the entire mass of the atom. Which is an
example of research that extended Rutherford's findings?
a. De Broglie viewed electrons exhibiting wave-like behavior.
b. Bohr concluded that electrons orbit the nucleus in set circular paths.
c. Chadwick determined the charge of the neutron to be neutral and its mass similar to
that of a proton.
d. Thomson determined that the atom consists of negatively-charged particles.
Answer:
c. Chadwick determined the charge of the neutron to be neutral and its mass similar to that of a proton.
Explanation:
The research that furthered Rutherford's work is the discovery made by James Chadwick who determined the nature of neutron.
Rutherford was inadequate to characterized the composition of the nucleus. This furthered the curiosity of Chadwick by which he discovered the neutrons. The mass of the neutrons is similar to that of the protonsTogether they account for the mass number of the atom. The neutrons do not carry any charges on them.How much more pressure does a 250 lb person exert on the ground than a 120 lb person if they are both standing on one foot with area 16 in2?
Answer:
57.124.18 Pascals
Explanation:
The pressure that each person exerts on the ground is given by:
Pressure = force/area
The force that each person exert is given by:
Force = mass (kg) x acceleration due to gravity (10 m/s2)
1 lb = 0.4536 kg, hence;
250 lb person = 113.398 kg
120 lb person = 54.431 kg
Force exerted by the 250 lb person = 113.398 x 10 = 1133.98 kg/m2
Force exerted by 120 lb person = 54.431 x 10 = 544.31 kg/m2
16 inch2 = 0.0103226 m2
Pressure exterted by 250 lb person = 1133.98/0.0103226
= 109,854.11 pascals
Pressure exerted by 120 lb person = 544.31/0.0103226
= 52,729.93 Pascals
Difference in pressure = 109,854.11 - 52,729.93
= 57,124.18 Pascals
Hence, a 250 lb person will exert 57.124.18 Pascals pressure more than a person of 120 lb on a foot with a 16 inch2 area.
How many atoms are in 8.2 moles of magnesium
Answer:
4.93804*10^24 atoms
Explanation:
Hope this helped!
If 240.0 g NaOH reacts, how many grams of Cu(OH)2 should precipitate out in the reaction? Show work
Answer:
292.7 g
Explanation:
Note: the reaction is missing but I looked it up on the web and found it.
Step 1: Write the balanced equation
CuSO₄(aq) + 2 NaOH(aq) → Cu(OH)₂(s) + Na₂SO₄(aq)
Step 2: Calculate the moles corresponding to 240.0 g of NaOH
The molar mass of NaOH is 40.00 g/mol.
240.0 g × 1 mol/40.00 g = 6.000 mol
Step 3: Calculate the moles of Cu(OH)₂ formed from 6.000 moles of NaOH
The molar ratio of NaOH to Cu(OH)₂ is 2:1. The moles of Cu(OH)₂ formed are 1/2 × 6.000 mol = 3.000 mol.
Step 4: Calculate the mass corresponding to 3.000 moles of Cu(OH)₂
The molar mass of Cu(OH)₂ is 97.56 g/mol.
3.000 mol × 97.56 g/mol = 292.7 g
To determine the density of an irregularly shaped object, a student immersed the object in 22.2 mL of water in a
graduated cylinder, causing the level of the water to rise to 37.8 ml. If the object had a mass of 22.4 g, what is the
density of the object?
Answer:
Explanation:
The density would be 4.
Question 14 Multiple Choice Worth 2 points) If we have less power, we most likely have A. the same amount of work being done over a shorter period of time B. more work done over a shorter period of time C. more work done over the same amount of time D. the same amount of work being done over a longer period of time
Answer:
its c
Explanation:
Answer:
A. the same amount of work being done over a shorter period of time
Explanation:
I believe. Sorry if it is incorrect.
A balloon is filled with 3.00 L of helium at a pressure of 765 torr. What is the volume of the balloon at an altitude where the pressure is 530 torr if the temperature remains constant
Answer:
4.33L
Explanation:
what is an atomic element of carbon
Answer: do u mean atomic number? The atomic number for carbon is 6
Explanation:
Answer:
Chemical element
Explanation:
Carbon is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust.
a pea plant which produces green pods is crossed with a pea plant which produces yellow pods. the resulting offspring had green pods. with respect to pod color the genotype of the offspring is most likely
Answer: the green plant probly was the more domanate with a gentype of TT or Tt
Explanation:
it took after the green plant make it more domanate
The term "genotype" can also reference towards the alleles or variations that an individual possesses. The green plant was most likely the most dominant, having a genotype of TT or Tt.
What is genotype?An organism's genotype is its whole collection of genetic material. The term "genotype" can also reference towards the alleles or variations that an individual possesses in a certain gene or genetic region. The amount of alleles a person can have in a particular gene is determined by the amount of duplicates of each chromosome contained in that species, which is also known as ploidy.
Diploid organisms, such as humans, have two complete sets of chromosomes, implying that each person possesses two alleles for each given gene. When both alleles are identical, the genotype is said to be homozygous. When the alleles were distinct, the genotype is called heterozygous. The green plant was most likely the most dominant, having a genotype of TT or Tt.
Therefore, the green plant was most likely the most dominant, having a genotype of TT or Tt.
To learn more about genotype, here:
https://brainly.com/question/10644243
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A _____________reaction mechanism involves loss of a leaving group, formation of a ________ followed by the removal of a proton (H ) from the adjacent Carbon.
A. electrophile
B. carbocation
C. E1
D. E2
E. nucleophile
Answer:
The correct answer is Option C (E1) and Option B (carbocation).
Explanation:
Intramolecular immunity idols are considered as that of the formation mechanism with E1 responses or reactivity. Reactants with E1 were indeed obligations of both parties, meaning that an E1 reaction was conducted thru all the two stages known as ionization but rather deprotonation. Involves the absence of either an aromatic ring, a carbocation has been generated throughout the ionization solution.Some other possibilities offered aren't relevant to the procedure outlined. So the above alternative is accurate.
Jada Peterson
Wanda often looks through her telescope at the details of different bodies in our solar system. What skill is Wanda using?
A:observing
O concluding
O experimenting
hypothesizing
Save and exit
1
Answer: A
Explanation:
The small intestine is over 30 feet in length! Why do you think the small intestine is so long
Answer:
Explanation:
Better digestion!!