Answer:
A. cycas
1. it is thick and scaly
2. it grow relatively slowly and have a large, terminal rosette of leaves.
B. bamboo
1. it is very durable
2. it is both flexible and elastic
C. lemna
1. it grows as simple free-floating thalli on or just beneath the water surface
2. it are small, not exceeding 5 mm in length
D. paddy
1. it is variety purity
2. it degree of purity
E. sugarcane
1. it is bear long sword-shaped leaves
2. it's stalks are composed of many segments, and in each joint there is a bud
NEED HELP ASAP PLZZZ
Answer:
Im pretty sure the answer is A. An electron moves from the FIFTH energy level down to the SECOND energy level.
Explanation:
What is the molarity of a 75.0 mL solution that contains 0.225 g of
potassium nitrate?
Answer:
M=0.0297M
Explanation:
we know that molarity equals number of mole of solute over the volume of solution.
M=n/V but n=m/M
n=0.225g÷101g/mol =0.00223mol
M=0.00223mol/0.075l
M=0.0297M
Answer:
0.0297M
Explanation:
We will use the formula M= moles of solute/lites of solution.
First we need to figure out the Moles of the solute, to get this we first need the molar mass of KNO3 (potassimum nitrate).
The Molar Mass of potassimum nitrate is 101.103 g/mol
K - 1 x 39.09
N - 1 x 14.006
O - 3 x 15.999
KNO3 - 101.103 g/mol
Now we get the moles of the solute by doing.
0225g/ 101.103g/mol = 0.00223 mol
Put the answer into the orginal equation to get 0.00223mol / 0.045 L
Which equals to 0.0297M. This is also the correct amount of significant figures.
Volcanoes will most likely form along a convergent plate boundary that is....
A. Continental vs Continental
B. Continental vs Oceanic
C. None of the above.
Answer:
I think its b part or none of above
1) How many moles of hydrogen gas can be produced if 0.57 moles of hydrochloric
acid, HCl, reacts with excess solid zinc according to the following chemical
equation?
2 HCl + Zn → Hz + ZnCl2
Answer: 0.28 mol H2
Explanation:
0.57mol HCl 1mol H2
2mol Hcl
Hydrochloric acid and zinc show the displacement reaction to produce hydrogen gas and zinc chloride. 0.57 moles of hydrochloric acid and excess zinc react to produce 0.28 mol H₂.
What is a displacement reaction?A displacement reaction is the removal of one of the elements from the reactant with highly active species of the reactivity species to produce the products. It can be a single or double displacement reaction.
The balanced chemical displacement reaction is given as:
2 HCl + Zn → H₂ + ZnCl₂
Here, two hydrochloric acids react with zinc to form one mole of hydrogen gas and one mole of zinc chloride.
Given,
Hydrochloric acid = 0.57 moles
Using proportions to calculate moles as:
If 2 moles of HCl = 1 mole H₂
Then, 0.57 moles = X moles
X = 0.57 ÷ 2
= 0.28 mol H₂
Therefore, 0.57 mole HCl produces 0.28 moles of hydrogen gas.
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What does the law of conservation of matter state?
a Matter can be created, destroyed, and changed.
b Matter can be destroyed and created, but not changed.
c Matter can be changed, but not created or destroyed.
d Matter can be created and changed, but not destroyed.
The answer is c. Matter can be changed, but not created or destroyed.
Help answer these chemistry questions
Answer:
45th answer is pure and properties 42 is periodictable
I get it! Now I know that an organism's traits
are controlled by ____________
Answer:
Genes mainly, however the environment as well
Explanation:
001 10.0 points
If you mix 4.5 g of HCl in enough water to
make 0.9 L (900 mL) of solution, what is the
molarity of the solution?
Answer in units of M.
Is it unbalanced or balanced if hydrogen reacts to iodine?
Answer:
unbalanced
Explanation:
because it is REACTing.
Identify the following element: a metal, 2 valence electrons, +2 oxidation number, valence electrons are in period 4.
Answer:
Calcium
Explanation:
I just checked the periodic table! This is right checked twice, I hope this helped first time answering a question. Good luck!
Can someone help me please
Answer: The correct pairs of elements likely to form ionic compounds are, potassium and sulfur, magnesium and chlorine. The answer is argon please give me brainlist
Explanation:
The molecular formula for a compound with a molar mass of 180.18g that contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass is
Answer:
C6H12O6
Explanation:
First you need to find the empirical formula by the percents that they're giving you. You assume that is 100 grams and if for example you have 40% of carbon you will have 40 grams of carbon.
1.Find the number of moles of each atom
C: 40g÷12g/mol= 3.33 mol
H: 6.7g÷1g/mol= 6.7 mol
O: 53.3g÷16g/mol= 3.33 mol
You divide all ratios by the minimum ratio and you obtain the empirical formula
CH2O
Since you're given the molar mass, you now have to find the molar mass of CH2O by adding the molar mass of each element present and repeated in the compound.
CH2O= 30g/mol
Now you know that the molar mass of the molecular formula we are looking for is 180.18 g/mol, and since the empirical formula is the molecular formula in its smaller ratio, by logic you can say that:
180.18g/mol ÷ 30g/mol= 6
So, you now know that the empirical formula is being multiplied by a factor of 6 to reach a compound with a molar mass of 180.18g/mol, so you multiply each subscript of the empirical formula by 6 obtaining:
C6H12O6
Can anyone pls answerrrrt
Answer:
wdym
Explanation:
hmm
What is the wavelength of the above wave?
Answer:
well what above wave?? do you have a picture
Explanation:
Food waste, like a feather or a bone, fall into food, causing
contamination.
Physical
Chemical
Pest
Cross-conta
Answer:
what do I need to do?..
..
Feather or bone when fall into food causing Physical contamination.
Food waste, like a feather or a bone etc fall into food causing Physical contamination because the contaminants such as feather and bone are mixed in the food physically not chemically. These contaminants can be removed through physical means such as with the help of hand.
Some contaminants mix with the food chemically means they react with the food and produce something new. Such type of contaminants are present in liquid form so we can conclude that feather or a bone etc when fall into food causing Physical contamination.
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What are the most important topics for revision in chemistry?
Answer:
structure of atom
states of matter
classification of elements and periodicity in properties
thermody namic
Equilibrium
Redox reacation
which statement describes how vapor pressure occurs? (1 point)
a) Some molecules of a substance have high enough kinetic energy to vaporize. These molecules exert
pressure on the substance.
b) Some molecules of a substance have low enough kinetic energy to melt. These molecules exert pressure on the substance
c) Some molecules of a substance have low enough kinetic energy to vaporize. These molecules exert
pressure on the substance.
d) Some molecules of a substance have high enough kinetic energy to melt. These molecules exert pressure on the substance
Some molecules in a substance have a high kinetic energy hence they are able to convert into vapor. These molecules exert pressure on the liquid surface.
We know that the molecules that compose matter are in constant random motion. The kinetic energy of all the molecules in the liquid are not the same. The molecules at the surface of the liquid posses more kinetic energy than the molecules below.
Some molecules of a substance have high enough kinetic energy to vaporize. These molecules exert pressure on the substance.
Learn more: https://brainly.com/question/25273232
Answer:
Some molecules of a substance have high enough kinetic energy to vaporize. These molecules exert pressure on the substance.
Explanation:
An aqueous solution has a volume of 2.0 L and contains 36.0g of glucose. If the Molar Mass of glucose is 180g/mol, what is the molarity of the solution
Convert grams of Glucose to moles of Glucose and then solve for Molarity
show all work.
Answer:
moles = 36/180 = 0.2 moles
molarity = 0.2/2 = 0.1 mol/dm3
Elements that are usually dull, brittle and do not conduct electricity are know as______.
Points: 46
Answer:
nonmetal
Explanation:
.........
...
.
help plz I don't understand the last 2 questions
Answer:
b) (i): 0.91 Amgstroms
(ii): 9.1 × 10^-11 Angstroms
(c): Volume = 20 Angstroms
Explanation:
• Let's first convert the units:
[tex]{ \rm{1 \:nanometre = 1 \times {10}^{ - 9} \: metres} } \\ { \rm{10 \: angstroms = 1 \times {10}^{ - 9} \: metres}} \\ { \rm{1 \: micrometer = 1 \times {10}^{ - 6} \: metres = 1000 \: nm}} \\ \\ { \rm{1 \: {nm}^{3} = 1000 \: {angstroms}^{3} }}[/tex]
Question (b)
(i)[tex]{ \rm{radius = \frac{diameter}{2} }} \\ \\ { \rm{radius = \frac{0.182}{2} }} \\ \\ { \rm{radius = 0.091 \: nm}} \\ \\ { \mathfrak{ answer{ : { \rm{radius = (0.091 \times 10) \: angstroms}}}}} \\ \\ { \rm{radius = 0.91 \: angstroms}}[/tex]
(ii)[tex]{ \rm{radius = 0.091 \: nm}} \\ \\ { \rm{radius = 0.091 \times( 1 \times {10}^{ - 9} ) \: metres}} \\ \\ { \rm{radius = 9.1 \times {10}^{ - 11} \: m }}[/tex]
(c)[tex]{ \rm{volume = (0.5 \times 0.2) \: nm \times 0.0002 \: micrometer}} \\ \\ { \rm{volume = 0.5nm \times 0.2nm \times (0.0002 \times 1000)nm}} \\ \\ { \rm{volume = 0.5 \times 0.2 \times 0.2 \: nm {}^{3} }} \\ \\ { \rm{volume = 0.02 \: nm {}^{3} }} \\ \\ { \rm{volume = (1000 \times 0.02) \: angstroms {}^{3} }} \\ \\ { \rm{volume = 20 \: angstroms}}[/tex]
Which of the following could be classified as producing a physical change?
A. Burning a candle
B. Leaving a bicycle outside to rust
C. Bending sheet metal
D. Toasting a slice of bread
Answer:
C. Bending sheet metal.
Explanation:
The metal is still intact. No change in chemical bonds have occurred.
Burning a candle is converting wax into heat, CO2 and carbon soot.
A rusting bicycle is converting goof iron, Fe, into iron oxide (rust, Fe2O3)
Toasting bread is more difficult to define. If the bread is just warmed, then it is physical. If it is toasted (browned/burned), then a few surface molecules have been converted into tasty carcinogens, my favorite poison.
what is the difference between hypertonic and hypotonic
calculate the speed of a train that travels 540 km in 9 hours
Answer:
s=d/t. d=540 t=9h
540÷90=6 km/h
explain the concept of kenetic molecular theory
Which of the following is an example of genetic engineering?
1.The sweetest honeydew melons are selected and the seeds extracted and planted for next year’s crop.
2.The strongest animals in a population survive and reproduce.
3.An exact replica of a frog is created from a body cell.
4.A gene is introduced into salmon to make them grow twice as fast.
Answer:
4. A gene is introduced into salmon to make them grow twice as fast.
in which time period did the first animals that could live both in water and on land appear
explain the electrolysis of MgCl2 in aqueous solution
During electrolysis, a current is passed through the molten MgCl2, and when this happens, the Mg2+ ions move to the negative electrode where they PICK UP OR GAIN ELECTRONS. This is reduction. The Cl- ions move to the positive electrode where they LOSE ELECTRONS. This is oxidation.
Which statement correctly describes the relationship between molecular structure, the strength of electrostatic forces between
molecules, and the boiling point of a substance? (1 point)
The boiling point of a substance affects the strength of electrostatic forces, which can affect the molecular
structure
The boiling point of a substance affects its molecular structure, which can affect the the strength of
electrostatic forces.
Molecular structure affects the strength of electrostatic forces, which can affect the boiling point of a
substance
Stronger electrostatic forces cause a stronger molecular structure and lower boiling points
Molecular structure affects the strength of electrostatic forces, which can affect the boiling point of a substance is the statement that correctly describes the relationship between these terms.
The molecular structure is the way in which the atoms that are in a molecule are arranged in space, this is defined by a series of forces that hold the atoms together in a specific arrangement.
The boiling point is the temperature at which the vapor pressure of the liquid equals the pressure that surrounds the liquid, when this happens, the liquid transforms into gas.
For a compound to vaporize, the forces that hold the molecules together must be broken, this means that the boiling point of a compound depends on the attraction between the molecules, that is, on the forces that determine the molecular structure.If the molecules are held together by strong electrostatic forces, it will take a lot of energy to push the molecules away from each other and the compound will have a very high boiling point.Therefore, we can conclude that the boiling point depends on the molecular mass of the substance and the type of electrostatic forces present, that is, the bonds that the atoms establish with each other to form the molecule (molecular structure).
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When no more solute will dissolve in a solvent, the solution is_________.
Answer:
saturated solution because it can only dissolve upto fixed temperature
Answer:
Saturated
Explanation:
Explanation from online:
"When the solution equilibrium point is reached and no more solute will dissolve, the solution is said to be saturated. A saturated solution is a solution that contains the maximum amount of solute that is capable of being dissolved."
Stay Safe, and I hope this helps!!!!
What is the frequency of the above wave?
Answer: is a measurement of how often a recurring event such as a wave occurs in a measured amount of time
Explanation:
