Answer:
group 3 and 12 alkali and alkaline earth metal
which option can be classified as a pure substance
A. solution
B. compound
C. homogeneous mixture
D. heterogeneous mixture
Answer:
B. compound
Explanation:
A pure substance can be an element, which consists of only one type of atom and cannot be broken down by a chemical change, or a compound, which consists of two or more types of atoms.
Iron reacts with oxygen and water to create rust and hydrogen gas as shown in the chemical equation. What mass of rust, to the nearest hundredth gram, is produced in this reaction?
A) 4.3 g
B) 5.8 g
C) 16.8 g
D) 29.4 g
Answer:
i think its 5.8
Explanation:
What is the mass of air in room
Answer:
the mass of the air in the room is 4.96512 kg ( in 0°C)
Sasha did an experiment to study the solubility of two substances. She poured 100 mL of water at 20°C into each of two beakers labeled A and B She put 50 g of
Substance A in the beaker labeled A and 50 g of Substance B in the beaker labeled B. The solution in both beakers was stirred for 1 minute. The amount of substance
left undissolved in the beakers was weighed. The experiment was repeated for different temperatures of water and the observations were recorded as shown.
Experimental Observations
Mass of Undissolved Substance at Different Temperatures (gram)
20°C
40 °C
60°C
80 °C
Substance
А
12
11
9
8 8
B
45
40
34
31
Part 1: Which substance has a higher solubility?
Part 2: Explain your answer for Part 1
Answer:
Answer temperatures gram is correct because there is more of a mass of numbers and the numbers are higher. (don't really know this subject, just guessing, hope this helped.)
The substance A has higher solubility then substance B because the higher the temperature the easier the substance will dissolve.
What is solubility?The word solubility is defined as the ability of a substance, the solute, to form a solution with another substance, the solvent.
It can also be defined as a property that allow sugar molecule to dissolve.
It can be defined as at a given temperature, the amount of solute that can dissolve in a given amount of solvent.
In this reaction, increasing the pressure and temperature results in increased solubility. An increase in pressure causes more gas particles to enter the liquid, lowering the partial pressure.
For exothermic reaction the temperature increases with decrease in solubility and for endothermic reaction the temperature decreases with increase in solubility.
Thus, the substance A has higher solubility then substance B because the higher the temperature the easier the substance will dissolve.
To learn more about solubility, refer to the link below:
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#SPJ5
which best explains why water dissolves most salts?
Answer:
where are the answers?
Explanation:
How many atoms of carbon are present in 4.10 moles??!
Answer:
2.4×1024 atoms.
Explanation:
Please mark me as brainliest
An endothermic reaction occurs when water and ammonium nitrate are combined. Which of the following statements correctly
describes the energy changes in the reaction?
OA. Energy is released because the reactants have more chemical energy than the products.
OB. Energy is absorbed because the reactants have more chemical energy than the products,
OC. Energy is absorbed because the products have more chemical energy than the reactants.
OD. Energy is released because the products have more chemical energy than the reactants.
Answer:
C.Energy is absorbed because the products have more chemical energy than the reactants.
Explanation:
What is a net ionic equation?
Do cells have atoms?
Answer:
Ye? everything is made up of atoms so sure
Select from the unit conversion factor options below to determine the mass in grams of 1.204 × 1024 atoms of carbon.
1 mol C/ 6.02 x 1023 atoms C, 6.02 x 1023 atoms C / 1 mol C
12 g C / 1 mol, 1 mol / 12 g C
a
12040 g
b
24 g
c
204 g
d
1.99 g
Answer:
option a is the answer
Explanation:
bye bye
Like the success of animals, the success of plants is limited based on the resources available to each individual. In the tropical
rainforest, plants are especially limited by the spate they have available to grow and reproduce. Which of these statements
describes a way that limited space will impact
the success of a plant in the rainforest? (SC.7.L.17.3)
A plant without enough space will face increased predation from herbivores
a
O A plant without enough space will not have as many parasites and diseases.
3
A plant without enough space will be more likely to be impacted by air quality
A plant without enough space will not be able to capture enough light to grow.
A plant without enough space to grow may be impacted by inadequate air as well as light for proper growth.
The competition for space in the tropical rainforest has impacts on two processes:
Light for photosynthesisAir for growthLight is very important for photosynthesis and the overall well-being of plants. In a tight space, light and air become limited. This means that plants growing in such a space will not be able to photosynthesize optimally.
Plant roots need air to function properly and when becomes inadequate, the entire plant becomes negatively impacted.
More on competition for space can be found here: https://brainly.com/question/9385889?referrer=searchResults
9. Any body of rock or sediment in which
water can flow and be stored is called a(n)
a. well.
b. aquifer.
c. sinkhole.
d. artesian formation.
Answer:
It's option b) Aquifer.
if you can’t already tell by the amount of questions i do not understand chemistry lol, giving brainliest
Answer:
Ok, so the process here is to convert the mass of H2 (hydrogen gas) to moles by dividing the mass by the molar mass of H2. Once you have the moles then you have to multiply by the STP (standard temperature and pressure) molar volume which should be 22.4.
Molar mass of H2 = (1.01)x2 = 2.02g/mol
19.3/2.02 = 9.55 moles
Now just multiply the moles by the molar volume
9.55 moles x 22.4 = 213.92 Litres of H2 are in 19.3g of H2
Is a change in color when combining two substances normally a sign of a chemical change or a physical change?
Answer:
Change in colour is a chemical change.
Explanation:
Because when two substances combine chemically, they create (a) new substance(s) that have/has different molecular structures from the parent substances, thus mostly likely absorb and reflect light in different ways.
What are the compounds that you can find in mayonnaise
HEY!
Mayonnaise is an oil in water (O/W) emulsion; ingre- dients are primarily vegetable oil, egg yolk, sodium chloride, water and vinegar. Its relative stability towards microbial spoil- age has been attributed to the high salt content (in the water phase) and low pH, due to the vinegar.
thank me later
carryonlearing
Why are earthworms called as “friends of farmers”? Answer in no less than 4 sentences
Answer:
Organic matter composted with earthworms, often known as vermicompost, has been demonstrated in studies to have disease-suppressing qualities. The earthworms loosen the soil and enrich it with humus. As a result, they are known as farmer's pals. They help the crops grow healthier and over the time have earned farmers trust.
Explanation:
Hope this helps in some way!
What is an allotrope?
a) The same atom with a different number of neutrons
b) A radioactive substance
c) An alternative form of an element
d) Diamond
Which statement about the Periodic Table is correct?
A Elements are arranged in order of decreasing proton number.
B Group number is the number of electron shells in atoms of the elements in the group.
C Group numbers can be used to predict the charges of ions.
D Metallic character increases left to right across a period.
answer :c
explanation :
group numbers can be used to determine the number of electrons in the outer most shell thus if the group numbers are above four then the elemnts are negative ions if less than four then posetive
Which of the following compounds has the general formula X3Y2?Which of the following compounds has the general formula X3Y2?
There are no above options to choose from so I am giving an example of a X3Y2 formula which is Magnesium nitride, the formula is Mg3N2.
50 POINTS PLEASE HELPP
Circle the compound that has the higher boiling point and explain why we see the
differences we do
Answer:
1. Ethane has a higher boiling point
2. Heptyne has a higher boiling point
3. Octane has a higher boiling point
Explanation:
1. Ethane has stronger intermolecular attractions (van der Waal's forces) than ethene and so has the higher boiling point.
2. The longer (and the straighter) the chain, the greater the opportunity for intermolecular interactions, and thus the greater the boiling point. You should look up these boilig points! n-Pentane has a normal boiling point of approx. 36 ∘C ; n-heptane boils at 98 ∘C .
3. Octane has a high boiling point, because its molecule contains 8 Carbon atoms, and with increasing molecular weight of hydrocarbon its boiling temperature increases.
6.23 X 10^6 KL + 5.34 × 10^6 kL
Leslie is a forensic scientist who is using the precipitin test at a crime scene. What
question is Leslie MOST likely trying to answer?
Answer:
How long has this blood been here?
Explanation:
Answer:
Leslie is a forensic scientist who is using the precipitin test at a crime scene. What question is Leslie MOST likely trying to answer?
Explanation:
Leslie is a forensic scientist who is using the precipitin test at a crime scene. What question is Leslie MOST likely trying to answer? got the answer from quilt
the high electrical conductivity of metals is primarily due to
High conductivity of metals is caused by electrons that are free to move through the lattice.
hope this helps!
What is an active metal?
A. a metal that reacts with oxygen
B. a metal that is above hydrogen in the activity series
C. a transition metal
D. a metal with only one valence electron
Answer:
A metal is said to be an active metal when it reacts strongly and quickly with other elements due to the electrons in its structure and its ease of sharing the electrons with other elements. ... A metal's reactivity increases as we go from the top to the bottom of the periodic table.
Explanation:
In a bond between potassium (K) and bromine (Br),
A.
the potassium atom will gain an electron and become smaller as a cation, while the barium atom will lose an electron and become bigger as an anion.
B.
the potassium atom will lose an electron and become smaller as an anion, while the barium atom will gain an electron and become bigger as a cation.
C. the potassium atom will gain an electron and become smaller as an anion, while the barium atom will lose an electron and become bigger as a cation.
D.
the potassium atom will lose an electron and become smaller as a cation, while the barium atom will gain an electron and become bigger as an anion.
Answer:
D (But as a heads up, you wrote barium instead of Bromine)
Explanation:
The Potassium atom will lose an electron since its valence shell only has one, while Bromine has 7 electrons in its valence shell. Potassium wants to get rid of its one electron, Bromine wants to gain that one electron to get a full shell.
Potassium will become a CATION with a positive charge (since it lost an electron), Bromine will become an ANION with a negative charge (since it gained an electron)
Describe the S-wave shadow effect of earth quakes.
Answer: The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent (refracted) by the liquid core.
Explanation: 104 to 140 degrees from a given earthquake
A 12.17 g sample of a compound contains 7.77 g of iron, Fe, 1.44 g of phosphorus, P, and oxygen, O. Calculate the empirical formula for the compound.
Answer:
Fe₃PO₄
Explanation:
They have given the total mass of the compound, the mass of iron and the mass of phosphorus. So we can find the mass of oxygen.
Mass of oxygen = 12.17 - (7.77 + 1.44) = 2.96g
So we can now find the empirical formula.
Element - mass - Mr - Mass÷Mr - Ratio - Simplest Ratio
Fe - 7.77g - 55.8 - [7.77÷55.8] - [0.14÷0.05] - 2.8 = 3
P - 1.44g - 31 - [1.44÷31] - [0.05÷0.05] - 1
O - 2.96g - 16 - [2.96÷16] - [0.19÷0.05] - 3.8 = 4
[The simplest ratio was obtained by dividing the answer of mass÷mr with the smallest value. Phosphorus had the smallest value of mass÷mr=0.05, so all other answer were divided by 0.05]
Emperical formula = Fe₃PO₄
Solve the following problems and show the complete solutions.
1. How many moles of Carbon Dioxide is equivalent to 1.5X1023 atoms of CO2?
2. If you have 5grams of pure Aluminum, (Al), how many atoms does it have? (Al=27)\.
3. If 3 moles Sodium (Na) reacts with exact Chlorine gas (Cl2) in this reaction: 2Na + Cl2 ---> 2NaCl How many mole of Sodium Chloride (NaCl) will be produced?
4. Give the mass percent composition of Potassium, Sulfur and Oxygen in a molecule of Potassium Sulfate: K2SO4.(atomic mass: K=39, S=32).
5. If 162g of Aluminum reacts with 144g of Oxygen gas to form Aluminum oxide, what is the mass percentage of Aluminum?
6. A sample was analyzed and found to contain 40% Carbon. 6.71% Hydrogen and 53.29% Oxygen. If the molecular mass of this compound is 18.16g/mol, what is the empirical and molecular formula of this compound?
The molecular formula of the compound is C6H12O6.
1) We know that;
1 mole of CO2 contains 6.02 X 10^23 atoms
x moles of CO2 contains 1.5 X 10^23 atoms
x = 1 mole X 1.5 X 10^23 atoms /6.02 X 10^23 atoms
x = 0.25 moles of CO2
2) 1 mole of pure Al has 27 g
x moles of Al has 5 g
x = 1 mole × 5 g/ 27 g
x = 0.19 moles
If 1 mole of Al contains 6.02 X 10^23 atoms
0.19 moles of Al contains 0.19 moles × 6.02 X 10^23 atoms /1 mole
= 1.14 X 10^23 atoms
3) From 2Na + Cl2 ---> 2NaCl;
2 moles of Na produces 2 moles of NaCl hence 3 moles of Na will also produce 3 moles of NaCl.
4) The molar mass of K2SO4 is obtained from;
2(39) + 32 + 4(16) = 78 + 32 + 64 = 174 g/mol
Now;
Percentage by mass of K = 2(39)/ 174 × 100/1 = 44.8%
Percentage by mass of S = 32/174 × 100/1 = 18.4%
Percentage by mass of O = 4(16)/174 × 100/1 = 36.8%
5) The reaction equation is;
4Al(s) + 3O2(g) ----> 2Al2O3
Total mass present = 162g + 144g = 306 g
Mass percent of Al = 162g/ 306 g × 100/1 =52.9%
6)
C - 40/12 H - 6.71/1 O - 53.29/16
C - 3.33 H - 6.71 O - 3.33
Dividing through by the lowest ratio
C- 3.33/3.33 H - 6.71/3.33 O - 3.33/3.33
C - 1 H - 2 O - 1
The empirical formula is CH2O
Now;
[12 + 2(1) + 16] n = 180.16
30n = 180.16
n = 180.16/30
n = 6
The molecular formula is C6H12O6.
Learn more about molecular formula: https://brainly.com/question/11588623
I need to right a journal entry for school but i don't know what to put Write a journal entry from the perspective of a particle of light,
called a photon. Your story should follow the photon as it
travels from a star in the Milky Way that is 25 light years away
from Earth, all the way to the eye of a young person gazing up
at the night sky through their bedroom window. Compose your
entry in complete sentences.
it is for my 5 grad sicenc
Answer:
here you go
Explanation:
someone help me on this but i still got a hundred
Using the periodic table, choose the more reactive nonmetal.
Br or As
Br and As:
Bromine is more reactive as reactivity increases on moving from left to right in p-block