3 points
18) A student determines the density of gold to be 20.9g/L. The true
density of gold is 19.30g/L. What is the student's percent error?round
answer to 2 significant figures *
Answer:
The answer is 8.29 %Explanation:
The percentage error of a certain measurement can be found by using the formula
[tex]P(\%) = \frac{error}{actual \: \: number} \times 100\% \\ [/tex]
From the question
actual density = 19.30g/L
error = 20.9 - 19.3 = 1.6
We have
[tex]p(\%) = \frac{1.6}{19.3} \times 100 \\ = 8.290155440...[/tex]
We have the final answer as
8.29 %Hope this helps you
The data table shows the number of pumpkin seeds that germinate at different temperatures. What is the median number of seeds that germinate at 24C?
A. 80.5 B. 82 C. 78.5 D. 80
Answer:
Explanation:
80
4. CHALLENGE Suppose you had a mixture of sand and small,
hollow beads. How might you separate the mixture?
I'm not sure if this is the answer but maybe oil.
In the acid-base mechanism, the base is a proton acceptor, and the acid is the proton donor. An acid-base reaction is visualized as the reaction in which proton transfer takes place. However, in a nucleophilic substitution reaction, the nucleophile attacks a substrate (usually an electrophile), and the leaving group is removed from the substrate as a weaker nucleophile. The nature of the reactants determines whether a reaction will proceed as an acid-base reaction or a nucleophilic substitution reaction. Classify each reaction as a nucleophilic substitution reaction or an acid-base reaction.
a. CH3CH2O-+CH3Br → CH3CH2OCH3+Br-
b. CH3CH2OH+HCl → CH3CH2Cl+H2O
c. CH3COOH+NaOH → CH3COONa +H2O
d. CH3CH2CH2Br+HCN→CH3CH2CH2CN+HBr
e. CH3CH2OH+KOH→CH3CH2OK +H2O
Answer:
a) nucleophilic
b) Acid-base
c) Acid- base
d) nucleophilic
e) Acid-base
Explanation:
A nucleophilic reaction is one in which a nucleophile attacks a substrate and a leaving group departs from the substrate.
Reactions (a) and (d) are nucleophilic reactions since the Br- is the leaving group in the both reactions.
Reactions (b) (c) and (e) are acid-base reactions since they involve salt and water as products.
What type of energy is defined as the kinetic energy of the atoms of a substance?
Explanation:Thermal energy, or heat, is the energy that comes from the movement of atoms and molecules in a substance. Heat increases when these particles move faster. Geothermal energy is the thermal energy in the earth. Motion energy is energy stored in the movement of objects.
I hope this helped!
why ice melt into water
Particle motion in ice is __________than partlice motion in water.
1. faster
2. slower
3. the same
Answer:
1. Faster
Explanation:
You need to make an aqueous solution of 0.192 M barium sulfide for an experiment in lab, using a 500 mL volumetric flask. How much solid barium sulfide should you add?
Answer:
Explanation:
Molecular weight of barium sulphide = 169
500 mL of .192 M barium sulfide = .5 x .192 moles of barium sulphide
= .096 moles of barium sulfide
= .096 x 169 gram of barium sulfide
= 16.22 grams of barium sulfide .
We shall have to add 16.22 gram .
Question 2 of 10 >
Nitrogen and hydrogen combine at a high temperature, in the presence of a catalyst, to produce ammonia,
8H8
N2(g) + 3 H2(g) — 2NH,(8)
Assume 0.170 mol N, and 0.561 mol H, are present initially,
After complete reaction, how many moles of ammonia are produced?
NH,
How many moles of H, remain?
Answer:
Moles of H₂ left = 0.051 mol
Moles of ammonia formed = 0.34 mol
Explanation:
Given data:
Moles of N₂ = 0.170 mol
Moles of H₂ = 0.561 mol
Moles of ammonia formed = ?
Moles of H₂ left = ?
Solution:
Balance chemical equation:
N₂ + 3H₂ → 2NH₃
Now we will compare the moles of ammonia with nitrogen because nitrogen is limiting reactant and limit the yield of ammonia.
N₂ : NH₃
1 : 2
0.170 : 2×0.170 = 0.34 mol
Moles of ammonia formed = 0.34 mol
Moles of H₂ reacted:
N₂ : H₂
1 : 3
0.170 : 3/1×0.170 = 0.51 mol
0.51 moles of hydrogen react with 0.170 moles of nitrogen.
Moles of H₂ left:
Moles of H₂ left = Total - moles reacted
Moles of H₂ left = 0.561 mol - 0.51 mol
Moles of H₂ left = 0.051 mol
Draw molecules that satisfy the following prompts:
1. All molecules must have a minimum of 12 Carbon atoms and exactly 3 heteroatoms (not carbon or hydrogen atoms).
2. You may not use the same molecule twice for any parts of this question.
4. You do not need to look up solubility information, but the answers must be reasonable (supported by the concepts that we have discussed). Also, the structures must be reasonable (improper structures, e.g. carbon with 5 bonds or oxygen with one bond and no charge, will not receive any credit).
a. Draw two non-charged molecules that will be separated once they are placed in a separatory funnel that contains 2.5 M HCl(aq) and dichloromethane.
b. Draw two non-charged molecules that will be separated once they are placed in a separatory funnel that contains 2.5 M NaOH(aq) and dichloromethane.
c. Draw two non-charged molecules that will be separated using neutral water and dichloromethane and in a separatory funnel.
Answer:
see images attached
Explanation:
Here we are trying to perform solvent extraction. In solvent extraction, there must be an aqueous phase and an organic phase.
One of the species to be separated is extracted in greater concentration in the aqueous phase while the other is extracted in greater concentration in the organic phase.
The phase into which each specie is extracted depends on the nature of the specie.
Two structures are shown in the images attached that will be separated by the methods shown in (a) (b) (c) in the question
6. Clownfish, sea anemone, coral, sea urchins, sponges and parrot fish are 5 points
just a few examples of the large variety of organisms that can be found in
a coral reef. The coral reef and its inhabitants (residents) are suffering due
to several factors such as pollution, coastal development, sedimentation
and destructive fishing practices. What would be the most likely result if
some of the species in the coral reef are destroyed? *
Answer:
The orange-and-white clownfish you know from Hollywood is only one of 30 species of clownfish that live in coral reefs around the world; small in size and big in personality, these tiny comedians have one of the most unique lifestyles in the reef. The orange-and-white clownfish you know from Hollywood is only one of 30 species of clownfish that live in coral reefs around the world; small in size and big in personality, these tiny comedians have one of the most unique lifestyles in the reef.
Explanation:
point being, it would be absolutely terrible
Coral reef are the biggest biodiversity in the world. Therefore, destruction of coral reefs definitely affect the aquatic livings. As well as it leads to erosion of seashore lines.
What are coral reefs?Corals reefs are the habitat of 25% of sea organisms. It means there are well over a million species that rely on coral reefs for their existence. The reef offers these organisms the vital food, habitat, and breeding grounds required for the survival of their species.
The marine biodiversity would suffer greatly if their homes vanished. And many fish, turtles, and other species would vanish in a domino-like fashion.
Coral reefs are threatened by a number of things, such as local threats like overfishing, destructive fishing methods, coastal development, pollution, and careless tourism, as well as global effects of climate change like warming seas and rising CO₂ levels in the water. Natural phenomena like hurricanes, El Nio, and diseases are also a threat to oral reefs.
Find more on coral reefs:
https://brainly.com/question/364711
#SPJ6
5. What gases was produced from decomposing hydrogen peroxide? What non-gaseous product formed from the reaction
Answer:
H2O
Explanation:
The equation for the decomposition of hydrogen peroxide is shown below;
2H2O2(l)-----> 2H2O(l) + O2(g)
Hence, the decomposition of H2O2 yields oxygen gas and water. Water is a non gaseous product of the reaction as clearly seen in the equation above.
A tree frog uses plants or trees for protection from the rain. The frog is protected from the rain and the tree is neither helped nor harmed
Calculate the mass (in g) of 2.60 x 10^23 molecules of PbSO 4. The molar mass of PbSO 4 is 303.27 g/mol.
Answers:
986 g
7.27 g
1.04 g
131 g
4.74 x 1049 g
Explanation:
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[14/10 12:55 p. m.] Vicky Acpo je je je
[14/10 1oppho q[15/10 8:15 a. m.]p t...
Which is an example of a current research focus in chemistry?
A. applying gene therapy to treat certain diseases
B. using hook-and-loop tape in the clothing industry
C. developing smoke detectors for common use
D. studying coal combustion as an energy source
Answer:
b is the correct answer
do not trust answer one
Explanation:
Each molecule of an olefin has at least:
a
one double bond
b
two double bonds
c
three double bonds
d
two or more single bonds
Answer:
a.
Explanation:
One double bond.
For example ethene CH2=CH2
____ KClO3 = ____ KCl + ____ O2
Answer:
2KCIO3=2KCI+3O2
Explanation:
1. equalize right side O with left side O- Right side we have 3 and left only 2 so we add 3 in front(on left side)(3*2=6 O on both sides)
2.we add 2 on right side so now we have 6 O on left and 6 O on right and 2KCI
3.Add 2 on right side KCI so on both sides we got 2 KCI
A black object appears black because it reflects all light , and does not absorb any light. True or False
Answer:
False
Explanation:
It is the other way round, a black object appears black because it absorbs all the wavelength of light and does not reflect any light.
A black bucket will appear black because, it absorbs all wavelength of light incident on it. No other wavelength is reflected from the surface of the body. A black color suggests that a body is not reflecting any color. Instead such a body absorbing all the colors. For a white object, they reflect all the wavelength that is incident upon them.Level 1 01 Which correctly pairs the outside particles with their charge? A. Electrons: Positive B. Protons: Positive C. Neutrons: Neutral D. Electrons: Negative
Answer:
D. Electrons: Negative.
Explanation:
Hello, happy to help you today!
In this case, by considering the Bohr's atomic model in which atom is composed by a nuclei containing both protons and neutrons which are positively and neutrally charged respectively and surrounding electrons assembled in orbits or levels of energy which are negatively charged in order to provide a balance to the atom, the correct statement is: D. Electrons: Negative. Also consider the Bohr's model on the attached picture.
My best regards to you!
When 435 J of heat is added to 3.4 g of olive oil that's at 21 Deg C, it's
temperature increases to 85 Deg C. Calculate the specific heat of Olive oil? Show work
Answer:
k Nishant
Explanation:
i don't know sorry but u can search in google
These are two metamorphic rocks.
Left: red and white rock with rounded grains and coarse texture. Right: flat, gray rock composed of thin layers.
Which statement about the rocks is accurate?
The rock on the right is foliated.
The rock on the left formed from granite.
The rock on the left is formed from cooled magma.
The rock on the right has randomly arranged grains.
Answer:
A. the rock on the right is foliated
Explanation:
because if you look at the image then you see that the rock is arranged in layers so you can see that it is a foliated rock and also I got it right on my quiz
HOPE IT HELPS!!!
As temperature decreases, what happens to particles in a material?
Particles become further apart / expand?
Particles become slippery / liquid?
Particles become closer together / contract?
Particles become sticky / plasma?
Answer:
Particles become closer together / contract?
Explanation:
as particles cool down in temp, the particles slow down and compress
how can you tell where sugar enters the blood stream
please help asap
Answer:
Sugar can't enter cells directly , so when blood sugar level rises, ... signal for the release of insulin into the bloodstream.
Explanation:
yes when the sugar enter the bloodstream it may slowly slowly effect in your body and it may causes diabetes
Phosphoric acid, which is commonly used as rust inhibitor, food additive and etching agent for dental and orthopedic use, can be synthesized using a two-step thermal process. In the first step, phosphorus and oxygen react to form diphosphorus pentoxide: P4(l)+5O2(g-2 P20s(g) In the second step, diphosphorus pentoxide and water react to form phosphoric acld P20(9)+3 H200 2H,PO40) Write the net chemical equation for the production of phosphoric acid from phosphorus, oxygen and water.
Answer:
P₄(l) + 5 O₂(g) + 6 H₂O(l) ⇒ 4 H₃PO₄(aq)
Explanation:
Phosphoric acid is synthesized using a two-step thermal process.
In the first step, phosphorus and oxygen react to form diphosphorus pentoxide. The corresponding chemical equation is:
P₄(l) + 5 O₂(g) ⇒ 2 P₂O₅(g)
In the second step, diphosphorus pentoxide and water react to form phosphoric acid. The corresponding chemical equation is:
P₂O₅(g) + 3 H₂O(l) ⇒ 2 H₃PO₄(aq)
We can get the net chemical equation by adding the first step, the second step multiplied by 2, and canceling what is repeated on both sides.
P₄(l) + 5 O₂(g) + 2 P₂O₅(g) + 6 H₂O(l) ⇒ 2 P₂O₅(g) + 4 H₃PO₄(aq)
P₄(l) + 5 O₂(g) + 6 H₂O(l) ⇒ 4 H₃PO₄(aq)
In which atmospheric layer is the ozone layer?
A.troposphere
B.mesosphere
C.stratosphere
D.thermosphere
Answer:
stratosphere
Explanation:
contains a high concentration of ozone in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere.
Answer:
stratosphere
Explanation: Most atmospheric ozone is concentrated in a layer in the stratosphere, about 9 to 18 miles (15 to 30 km) above the Earth's surface. Ozone is a molecule that contains three oxygen atoms.
On average, about ____________ of incoming solar radiation is reflected back to space.
A 50%
B 30%
C 20%
D 10%
What is the frequency of a wave having 4.90 x 10 -12 J of energy?
Answer:
The answer is
[tex] \huge 7.40 \times {10}^{21} Hz[/tex]
Explanation:
To find the frequency of the wave we use the formula
[tex]f = \frac{E}{h} \\ [/tex]
where
E is the energy
f is the frequency
h is the Planck's constant which is
6.626 × 10-³⁴ Js
From the question
E = 4.90 × 10-¹² J
So we have
[tex]f = \frac{4.90 \times {10}^{ - 12} }{6.626 \times {10}^{ - 34} } \\ [/tex]
We have the final answer as
[tex]7.40 \times {10}^{21} \: \: Hz[/tex]
Hope this helps you
Plz answer me will mark as brainliest
Answer:
Compared to the walls of the right ventricle, the walls of the left ventricles are much thicker.
The plasma carries hormones, which are the body's chemical messengers.
If 0.4743 moles of H2O are produced, how many grams of VOCl3 will also be produced?
(V2O5 + 6 HCl → 2 VOCl3 + 3 H2O)
Answer:
i hope this helps. sorry if it totally doesn't
Discuss the relationship between atoms, elements and compounds. Include in your discussion if these are mixtures or pure substances and why.
Answer:
Elements are the simplest complete chemical substances. Each element corresponds to a single entry on the periodic table. An element is a material that consists of a single type of atom. Each atom type contains the same number of protons.
Chemical bonds link elements together to form more complex molecules called compounds. A compound consists of two or more types of elements held together by covalent or ionic bonds.
Explanation: