Answer:
Scientists were unsure about the last common ancestor between apes and humans because fossils are so scarce, researchers do not know what the last common ancestors of living apes and humans looked like or where they originated.
Explanation:
What are carbohydrates?
A. a type of base
B. a type of glyceride
C. a type of macromolecule
D. a type of amino acid
Answer:
a
Explanation:
me say so
Answer:
C
Explanation:
water, soil, temperature, space
Answer:
wdym??
Explanation:
Answer:
wdym by water, soil, temperature, space?
PLEASE HELP
Referring to the energy diagram below which arrow segment represents the activation
energy of this reaction?
O Arrow B
O Arrow D
O Arrow A
O Arrow C
Answer:
Arrow B
Explanation:
What is the single replacement reaction of Zinc + Lead(iv) Chloride
Answer:
[tex]2Zn+PbCl_4\rightarrow 2ZnCl_2+Pb[/tex]
Explanation:
Hello there!
In this case, when referring to single replacement reactions, it is crucial for us to figure out the formula of the starting reactants; thus, we know zinc is Zn and lead (IV) chloride is PbCl₄. In such a way, the reaction proceeds as follows:
[tex]Zn+PbCl_4\rightarrow ZnCl_2+Pb[/tex]
Which must be balanced as shown below:
[tex]2Zn+PbCl_4\rightarrow 2ZnCl_2+Pb[/tex]
Regards!
Please help!!!! Best answer will get brainliest
Answer:
covalent network
Explanation:
trust me on this one
is smoke a compound or a mixture? explain your answer.
Explanation:
hope it is helpful to you ☺️
. Water is one of our most important resources. Only about 1% of the Earth's water is for human needs. Name four ways you can help conserve water. This is for science btw...
Answer:please see explanation for answers
Explanation:
Water conservation is an approach geared towards controlling how water is used. Because of the ever growing population, which weighs so much on water available to mankind,Over negligence and abuse of our water resources have been a great point of concern, that is why the need for the knowledge of water conservation is preached.
Now, some of the ways we can conserve water include
1. Putting off taps while lathering the hands with soap
2.use of irrigation system to water crops and plants
3.. while brushing, make sure to turn off the tap or faucet
4. use a shower rather than a bath
A mass of 68.45 g of nickel (II) sulfate hydrate, NiSO4∙ nH2O, loses 28.40 g upon dehydration. What is the hydration number of this compound? (Find n.)
Answer:
n=4
Explanation:
n= (154.75×28.40)÷(68.45×18)
n=3.5
n=4(approximately)
5) How many Kilograms are in 12 L of Chlorine Gas?
Answer: 0.03798 kilograms
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given volume}}{\text {Molar Volume}}=\frac{12L}{22.4L}=0.535moles[/tex]
1 mole of chlorine gas [tex](Cl_2)[/tex] weighs = 71 g
Thus 0.535 moles of chlorine gas [tex](Cl_2)[/tex] will weigh = [tex]\frac{71}{1}\times 0.535=37.98g=0.03798kg[/tex] (1kg=1000g)
Thus there are 0.03798 kilograms in 12 L of chlorine gas.
Alternative fuel sources such solar and wind energy are gaining popularity and replacing fossil fuels in many applications. While there are many positive benefits to this technology, what negative impacts do they present?
Answer:
Environmental limitations.
Explanation:
The nonrenewable sources of energy include coal, oil natural gas, and nuclear power. While the renewable source of energy include tidal, solar, geothermal, and wind power. All the sources of nonrenewable energy are called fossil fuels. There are many positives of this alternate energy such as clean and clear energy. Though there may be some negative impacts such as land use changes for setting up solar panels, and windmill farms. These techniques are costly to maintain and implement in all sectors.What does the line with “alternating spikes and semicircles” mean?
Answer:
The line with spikes and semicircles is a stationary front, it brings days of steady rain.
Explanation:
L means Low pressure, it brings stormy weather with strong winds.
H means High pressure, it brings fair weather and light winds.
The line with spikes is a cold weather front, it brings thunderstorms and colder
temperatures.
The line with spikes and semicircles is a stationary front, it brings days of steady rain.
The first organisms to arrive in an ecosystem?
An artificial biosphere is an enclosed area that contains the elements necessary for human life to exist. Suppose scientists want to develop an artificial biosphere on a new planet. The new planet has an atmosphere that is 96% carbon dioxide with only trace amounts of oxygen. What could humans do to make enough oxygen to survive? Explain your answer.
Answer:
See Explanation
Explanation:
A biosphere is a zone of life found on earth. Since the artificial biosphere has all the elements that support and sustain human life, then there must also be soil in the artificial biosphere.
If that is the case, then we can engage in massive tree planting. Trees take in carbon dioxide and release oxygen. Hence if a large number of trees are planted all over the artificial biosphere, the trees will eventually produce large enough oxygen to support human life overtime.
Two glass rods are rubbed together. One of the glass rods are brought near (but
does not touch) an uncharged pith ball. Would you expect the pith ball to attract,
repel, or do nothing? Explain why.
Answer:
Do Nothing
Explanation:
Charges are transferred by friction when two different types of bodies are rubbed together. This is known as charging by friction.
However, when two materials of the same type are rubbed together, no charge is transferred from one object to the other hence there is no transfer of charges by friction and none of the two glass rods are charged.
Therefore, when one of the glass rods is brought close but does not touch the pith ball, nothing happens.
A toy balloon is filled to 135 mL at a temperature of 22.5 °C (295.5 K). What temperature in Kelvin does it need to be heated to expand to 250 mL?
Answer:
T2 = 547.2K
Explanation:
Given:
V1 = 135 ml. V2 = 250 ml
T1 = 295.5K. T2 = ?
Using Charles's law and solving for T2,
V1/T1 = V2/T2
T2 = (V2/V1)T1
= (250 ml/135 ml)(295.5K)
= 547.2K (or 273.2°C)
How many moles of KCl are produce when 61.5 g of KClO3 are decomposed?
Answer:
0.502mol
Explanation:
The balanced chemical equation of the reaction described in this question is as follows:
2KClO3 → 2KCl+ 3O2
According to the equation above, 2 moles of KClO3 will produce 2 moles of KCl.
Using mole = mass/molar mass to convert mass of KClO3 to moles
Molar mass of KClO3 = 39 + 35.5 + 16(3)
= 39 + 35.5 + 48
= 122.5g/mol
mole = 61.5 g ÷ 122.5g/mol
mole = 0.502mol
Since 2 moles of KClO3 will decompose to produce 2 moles of KCl.
0.502 mol of KClO3 will decompose to produce 0.502 × 2/2
= 0.502mol of KCl.
Which product is made from nonmetallic mineral resources?
a. Stainless steel
b. iron nails
c. Copper wires
d. concrete
Answer:
Concrete
Explanation:
Explain how the percentages of nitrogen , oxygens and carbon dioxide in the earth atmosphere today have changed from the earth
Answer:
See below
Explanation:
The atmosphere of the earth hundreds of millions of years ago was only water vapour and carbon, both from the one ocean that existed around the continental body of Pangea. The photosynthesis process and exache (⊕) caused the percentages to decrease.
What type of wave has the SHORTEST wavelength and the highest frequency?
Answer:
The answer is gamma rays.
Explanation:
Gamma rays have the highest energies, the shortest wavelengths, and the highest frequencies on the electromagnetic spectrum.
31. A mixture with sand, pink sugar and water would be best separated using
Answer:
Filtration and evaporation
Explanation:
A mixture of sand, pink sugar and water can be separated by filtration and evaporation.
The pink sugar is already dissolved in the water but the sand remains undissolved in the water hence it can be filtered off. The filtrate now contains the sugar.
The sugar is obtained from the filtrate by evaporation of the solution to yield the solid pink sugar and steam which can be condensed again to give liquid water.
Why do you think certain countries favored military solutions to the great depression while other contries did not
Answer:
The answer is below
Explanation:
Certain countries like Germany under Adolf Hitler favored military solutions to the great depression because the government felt that having a mass production of military weapons and recruitment of unemployed people or citizens into the army would change the dire situation.
On the other hand, countries like the United States did not favor the military solutions but instead choose the NEW DEAL under Franklin D Roosevelt; the reason could be linked to their democratic culture, the isolation belief tendency.
What is the mass number and atomic number of Ca0
Answer:
56.0774g/mol
Explanation:
hope you like it ☺️
Convert 6.71 moles NH3 to number of molecules.
Answer: There are [tex]40.41 \times 10^{23}[/tex] molecules present in 6.71 moles of [tex]NH_{3}[/tex].
Explanation:
Given: Moles of [tex]NH_{3}[/tex] = 6.71 mol
According to the mole concept, 1 mole of every substance contains [tex]6.022 \times 10^{22}[/tex] molecules.
Therefore, molecules present in 6.71 moles are calculated as follows.
[tex]Molecules = moles \times 6.022 \times 10^{23}\\= 6.71 \times 6.022 \times 10^{23}\\= 40.41 \times 10^{23}[/tex]
Thus, we can conclude that there are [tex]40.41 \times 10^{23}[/tex] molecules present in 6.71 moles of [tex]NH_{3}[/tex].
How many formula units are in 325 grams of iron (III) chloride?
Answer:
1.204 × 10^24 formula units
Explanation:
Using the following formula to convert mass of iron (III) chloride to moles;
mole = mass/molar mass
Molar mass of FeCl3 = 56 + 35.5(3)
= 56 + 106.5
= 162.5g/mol
Mole = 325/162.5
mole = 2mol
Next, to calculate the formula units of FeCl3, we multiply the number of moles of FeCl3 by Avagadro number (6.02 × 10^23)
Formula units of FeCl3 = 2 × 6.02 × 10^23
12.04 × 10^23
= 1.204 × 10^24 formula units.
If 125 mL of 0.56 MH2SO4, is diluted to a volume of 0.250 L, what is the molarity of the resulting solution?
Answer:
0.28M H2SO4
Explanation:
The molarity of a solution is defined as the ratio between the moles of the solute (In this case, H2SO4) and its volume in liters.
In the problem, the volume of the solution is increased from 125mL to 250mL. That means the solution is diluted:
250mL / 125mL = 2 times.
As the solution is diluted 2 times, the concentration is decreased in 2, that is:
0.56M / 2 =
0.28M H2SO4How many grams of Mg would be needed to react with 6.0 moles HCl?
Answer:
72g
Explanation:
The balanced equation of the reaction between Magnesium (Mg) and hydrochloric acid (HCl):
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
Based on this equation, 1 mole of Mg needs to react with 2 moles of HCl.
Hence, 6 moles of HCl will need to react with 6 × ½ = 3 moles of Mg.
Using the formula; mole = mass/molar mass
Molar mass of Mg = 24g/mol
3 = mass/24
mass = 72g.
What effect does the Earth's surface have on solar radiation?
Answer:
Thus, the proportion of Earth's surface that is covered by ice and snow affects how much of the Sun's solar radiation is absorbed, warming the planet, or reflected. Therefore, snow and ice which are covered in soot from pollution no longer reflect sunlight, but absorb it and so melting increases.
Answer:
Half of the solar radiation is absorbed and converted to infrared (heat).
Explanation:
If you stay at 90 degrees Celsius and a gas in a liquid solution has a pressure of 2 atm, what solubility should it have if it has a solubility of 64 g/L at a pressure of 8 atm?
Answer:
im not sure
Explanation:
Identify the element that cannot participate in nuclear fission reactions. (Hint: Think about the size of the atom.)
A.
hydrogen
B.
uranium
C.
thorium
D.
plutonium
i would appreciate it if someone could show me the net ionization reaction for the following equation:
CaCl2(aq) + 2NaHCO3 -> CaCO3 + 2NaCl + CO2 + H2O
thanks in advance!!
Answer:
Deduce the balanced chemical equation:
CaCO3(s) + 2HCl(aq) > CaCl2 + H2O(l) + CO2(g)
2. Write as ionic species:
Ca2+(aq) + CO3 2- (aq) + 2H+ + 2Cl- > Ca2+(aq)+ 2Cl-(aq) + H2O(l) + CO2(g)
3. Identify ions on the right that also appear on the left, and eliminate them. (As Robert Cruikshank says, these are known as ’spectator ions’ and take no overall part in the reaction):
CO3 2- (aq) + 2H+(aq) > H2O(l) + CO2(g)
This is the balanced ionic equation.