Answer:
Explanation:
Local unit means a county, city, village, or township.
a. For a chemistry lab final exam, a high school chemistry student was given a 1-mole sample of CaCl2 and a 1-mole sample of MgCl2 but was not told which sample was which. He was to identify the powders.
He looked up the enthalpies of formation for both of the chemicals and calculated the ΔHreaction for dissolving each powder: CaCl2 (s) Ca 2+ (aq) + 2Cl – (aq), and MgCl2 (s) Mg 2 (aq) + 2Cl – (aq). He then put each powder in a coffee-cup calorimeter and added water.
When sample A dissolved, the temperature increased by 0.74°C. When sample B dissolved, the temperature increased by 0.39°C. Which chemical was A, and which was B? Use the table of enthalpies of formation to help you. Explain your reasoning.
Ca^2+ ion is smaller than Mg^2+ ion hence it has a greater heat of formation or lattice energy.
When a crystal lattice is formed, the energy that is released if the component ions of the compound are brought together from infinity is called the lattice energy. It is the energy released when a crystal lattice is formed from its component ions.
The question lets us know that the heat released by the compounds depends on the energy released upon formation of the compound. Hence, the higher the energy released upon formation, the higher the magnitude of heat released upon dissolution of the compound.
Recall that lattice energy depends on the size of the ions. Thus, the smaller the ions, the higher the lattice energy.
Ca^2+ is smaller than Mg^2+ hence more energy is given off when CaCl2 is formed than when MgCl2 is formed.
As stated above, the greater the lattice energy, the greater the heat released when the lattice dissolves and the higher the rise in temperature.
Putting all these together, Sample A must be CaCl2 while sample B must be MgCl2.
https://brainly.com/question/2815368
Convert 500.45 g to kg (do not use Scientific Notation)
Answer:
To convert grams to kilograms, you divide the number of grams you have by 1000. So, 800 g = 800/1000 = 0.8 kg.
Explanation:
what charge does an atom that has lost electrons have?
Answer:
when an atom loses electrons, it will then contain more protons. Thus, the charge of the atom become positive.
What temperature scale is used in the ideal gas equation
Answer:
kelvin scale?
Explanation:
i`m not 100% on this one
What is the volume occupied by 2.34 grams of CO2 gas at STP?
Answer:
The volume occupied by 2.34 grams of CO2 gas at STP is 1.18 L
Which compound in 1 mol/dm3 solution has the highest PH value? a) Ethanoic acid b) Sodium chloride c) Sodium hydroxide d) Hydrogen chloride
Answer:
Explanation:
A. Ethanoic acid-acetic acid being weak acid dissocated weekly and turns solution to weakly acidic, ph will be between 4-7,
B. Hydrochloric acid - the solution would be acidic- with lots of H+ ions, Ph will be between 1-4,
C. Sodium chloride - solution prodcued netural Na+ and Cl- hence wont affect ph of solution will be equalt to 7.
D. Sodium hydrogen carbonate-NaHCO3 is weak base and the PH will be above 7,
A precipitation reaction 2. A Lewis acid-base reaction the produces a coordination complex: A Lewis acid-base reaction the produces a coordination complex 3. An oxidation-reduction reaction that is also a synthesis reaction: An oxidation-reduction reaction that is also a synthesis reaction Column B a. Pb2 (aq0 CrO42-(aq) --> PbCrO4(s) b. 2 Mg(s) O2(g) -> 2 MgO(s) c. Ag (aq) 2NH3(aq) --> [Ag(NH3)2] (aq)
Answer:
Pb2+ (aq) + CrO42-(aq) --> PbCrO4(s) - A precipitation reaction
2 Mg(s) + O2(g) -> 2 MgO(s) - An oxidation-reduction reaction that is also a synthesis reaction
Ag^+ (aq) + 2NH3(aq) --> [Ag(NH3)2]^+ (aq) - A Lewis acid-base reaction the produces a coordination complex
Explanation:
A precipitation reaction is one in which two aqueous reactants yields an insoluble product called a precipitate as shown in reaction 1 above.
In the second reaction Mg is oxidized from zero to + 2 while oxygen was reduced from zero to -2 as the MgO is formed hence the reaction is an oxidation-reduction reaction that is also a synthesis reaction.
In the third reaction, Ag^+ a Lewis acid reacts with NH3, a lewis base to yield the complex [Ag(NH3)2]^+.
What is the balanced form of the chemical equation shown below?
C2H5OH() + O2(9)
H2O() + CO2(9)
A. C2H5OH() + 302(9) — 3H20() + 2002(9)
B. 2C2H5OH() + O2(g) – 5H20(1) + CO2(g)
C. C2H20(1) + 202(9)
-
H20(1) + 2C02(9)
D. C2H5OH() + O2(g) → H20(1) + CO2(g)
Answer:
C2H5OH +3O2 = 2Co2+ 3H2O
Explanation:
The balanced chemical equation is C2H5OH + 302 → 3H20 + 2CO2.
What is balanced chemical equation?A balanced chemical equation is one in which the count of atoms in all of the molecules is equivalent on both sides of the equation. The balancing of a particular chemical equation is governed by the Law of Conservation of Mass.
Balancing chemical equation is shown as below:
It can be seen that the count of carbon atom in left side 2 on the other hand the count of carbon in right side only one. By multiply with 2 in right side of the reaction , equation will be balanced.
Therefore, the balanced chemical equation is C2H5OH + 302 → 3H20 + 2CO2.
To know more about balanced chemical equation .
https://brainly.com/question/15052184.
#SPJ2
Cellular respiration occur within ______ of a cell.
Answer:
The mitochondria
Explanation:
Its where cellular respiration occurs
calculate the volume of the object immersed in the water in the water in the adjoining figur.
Answer:
100 cm³
Explanation:
Hi there!
Subtract:
400 cm³ - 300 cm³
= 100 cm³
Therefore, the volume of the object is 100 cm³.
I hope this helps!
500kg, 42m, 675g, and 10m/s are all examples of what typed of data?b
500kg, 42m, 675g, and 10m/s are all examples of a: continuous data.
A numerical data can be defined as a data set that is expressed in numbers only or a data set consisting of numbers rather than words. A numerical data is also known as a quantitative data.
Generally, numerical data are classified into two (2) main categories and these are;
Discrete data: a discrete data is a data set in which the number of possible values are either finite or countable. Some examples are; the value of a fair die, number of pen in a box, number of eggs in a crate, etc.Continuous data: a continuous data is a data set that has infinitely many possible values and as such those values cannot be counted, which simply means they are uncountable. Any data (quantity) such as mass, height, volume, weight, density, velocity, length, pressure, temperature, speed, distance, time are generally classified as continuous data.In conclusion, mass (500 kg), height (42m), mass (675g), and speed (10m/s) are all examples of a: continuous data.
Find more information: https://brainly.com/question/96076
3 point different between reactant and product
Answer:
reactants
The substance(s) to the left of the arrow in a chemical equation are called reactants. A reactant is a substance that is present at the start of a chemical reaction
Explanation:
product_The substance(s) to the right of the arrow are called products . A product is a substance that is present at the end of a chemical reaction. In the equation above, the zinc and sulfur are the reactants that chemically combine to form the zinc sulfide product.
There is a standard way of writing chemical equations. The reactants are all written on the left-hand side of the equation, with the products on the right-hand side. An arrow points from the reactants to the products to indicate the direction of the reaction:
reactants → products
Reactants
1. The substances used as starting materials and which react with one another are reactants.
2. Example: In this reaction Mg and O2 are reactants.
Products
1. The substances which are formed as a result of reaction are products.
2. Example: In this reaction MgO is a product.
Sarah measures out 151 grams of SO2. How many moles is this? Express your answer to three significant figures.
Answer:
[tex]\boxed {\boxed {\sf 2.36 \ mol \ SO_2}}[/tex]
Explanation:
We are asked to convert grams to moles. We will use the molar mass and dimensional analysis to perform this conversion.
1. Molar MassThe molar mass is the mass of 1 mole of a substance. These values are found on the Periodic Table because they are equivalent to the atomic masses, but the units are grams per mole instead.
We are given a mass of sulfur dioxide (SO₂). Look up the molar masses of the individual elements.
Sulfur (S): 32.07 g/mol Oxygen (O): 15.999 g/molNotice that the formula of the compound contains a subscript. The subscript after O means there are 2 moles of oxygen in 1 mole of sulfur dioxide. We must multiply oxygen's molar mass before adding sulfur's.
O₂: 15.999 * 2 = 31.998 g/mol SO₂= 32.07 + 31.998 = 64.068 g/mol2. Convert Grams to Moles
Now we will use dimensional analysis to convert grams to moles. From the molar mass, we know there are 64.068 grams of sulfur dioxide per mole, so we can set up a ratio.
[tex]\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}[/tex]
We are converting 151 grams to moles, so we multiply by this value.
[tex]151 \ g \ SO_2 *\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}[/tex]
Flip the ratio so the units of grams of sulfur dioxide cancel.
[tex]151 \ g \ SO_2 *\frac {1 \ mol \ SO_2}{64.068 \ g \ SO_2}[/tex]
[tex]151 *\frac {1 \ mol \ SO_2}{64.068 }[/tex]
[tex]\frac {151}{64.068 } \ mol \ SO_2[/tex]
[tex]2.356870825 \ mol \ SO_2[/tex]
3. RoundThe original measurement of grams (151) has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place. The 6 in the thousandth place tells us to round the 5 in the hundredth up to a 6.
[tex]2.36 \ mol \ SO_2[/tex]
151 grams of sulfur dioxide is approximately 2.36 moles of sulfur dioxide.
Question 14 (Essay Worth 10 points) (03.05 MC) Use complete sentences to differentiate between acids and bases on the basis of touch. Give an example of each type.
Answer:
Acid is a molecule capable of donating hydrogen ion and they form aqueous solutions with a sour taste while base is a substance that accepts proton from proton donor and in aqueous solution, they have an astringent or bitter taste. Moreover, a good example for base is sodium hydrogen carbonate as baking soda or baking powder and for acid, the most common example is the acetic acid or vinegar.
Answer:
Well, for starters, bases mostly consist of soaps and cleaning products, acids consist of vinegar,lemon,and stuff like that. Most acids on the basis of touch can burn your skin or be very sour, unlike bases which are more soapy and have a cleaner touch.A good example of an acid is vinegar, which can be used for cleaning but can also be used for making foods, on the other hand. A good example of a base is dish soap. It is used for cleaning.
Explanation:
i just did the exam and got a 100
help pls I really need the answer I will brainlest
Answer:
Latitude: the angular distance of a place north or south of the earth's equator, or of a celestial object north or south of the celestial equator, usually expressed in degrees and minutes. (Left to right)
Longitude: the angular distance of a place east or west of the meridian at Greenwich, England, or west of the standard meridian of a celestial object, usually expressed in degrees and minutes. (Up and down)
list three factors that affect the rate of a chemical reaction
Answer: 1) temperature, 2) add a catalyst, and 3) concentrations
Explanation: A rise in temperature adds kinetic energy to the reactants, leading to more frequent, and energetic collisions, which will often accelerate the reaqction. A catalyst is an agent that helps the reaction move forward more quickly by offering a substrate that aids in orienting the reactants for more efficient reaction. A higher concentration increases the chances of collisons that result in products.
write its IUPAC name?
Answer:
Hello
please make sure that there is any group which is join with alkane
Suppose 'A' is a liquid aromatic compound with molecular weight 78 and burns with sooty flame. a.Give the name of the compound 'A' b.write the molecular structure of 'A' C. What is the product when 'A' is treated with ? i.conc.HNO3 with conc.H2SO4 as catalyst ii.Halogen (cl2)in presence of sunlight and mention the use of the product obtained
Aromatic compounds are compounds that contain carbon-carbon multiple bonds.
The question did not mention that a heteroatom is present in the compound so we can assume that there is none of such. In that case, the compound contains only hydrogen and carbon.
So,
(CH)n = 78
where n is the number of each atom present.
(12 +1)n = 78
n = 78/13
n = 6
The molecular formula of the compound is C6H6
When C6H6 is treated with .conc.HNO3/conc.H2SO4 the compound shown in image 1 is formed. The reaction occurs at the C-C multiple bond.
When C6H6 is reacted with chlorine in the presence of sunlight, hexachlorobenzene (shown in image 2 attached) is formed.
https://brainly.com/question/24305135
12. State duplet and duplet rule. Explain in brief with examples .
Answer:
I HOPE THE ABOVE INFORMATION WILL HELP YOU A LOT.
ii)The outer electronic configuration of an element is 3d8 4s2
.To which group and period it belongs?
Answer:
group ten period four. that's the answer
Complete and write net ionic equation:
NH3 + HCI->
Answer:
IONIC EQUATION OF NH3 AND HCL IS NH4CL
Oxide of nitrogen that is acidic
Answer:
Nitrogen oxides are used in the production of nitric acid, lacquers, dyes, and other chemicals. Nitrogen oxides are used in rocket fuels, in the nitrification of organic chemicals, and in the manufacture of explosives.
Explanation:
why metals are not often used to
make clothes
Answer:
They would be to heavy and you would be really stiff
Explanation:
Imagine walking in a suit made of iron or tin
You would feel like the Tin Man
You would be stiff
Metals are hard and heavy
what is the name of this organic molecule
Answer:
C2H4 Ethylene
Explanation:
Hope it helps! :)
Which statement is true?
A. In an exothermic reaction, the energy of the products is the same as the energy of the reactants.
B. In an endothermic reaction, the energy of the products is the same as the energy of the reactants.
C. In an endothermic reaction, the energy of the products is greater than the energy of the reactants.
D. In an exothermic reaction, the energy of the products is greater than the energy of the reactants.
Exothermic reaction is where there is release of energy during a reaction
The enthalpy of exothermic reaction is negative
The relation between energy of products, reactants and enthalpy of reaction is
Enthalpy of reaction = sum of enthalpy of formation of products - sum of enthalpy of formation of reactants .
As enthalpy of reaction is negative, it means the enthalpy of products is less than the enthalpy of reactants so answer is :
In an exothermic reaction the energy of the product is less than the energy of the reactants.
C.
An endothermic reaction is a reaction that absorbs heat from the surroundings. That means that the energy of the system must increase. Therefore, the answer must be C as the products should have higher energy than the reactants.
Calculate the weight of CuO formed when 200g of Copper carbonate is heated.(Atomic weight of Copper-64,Carbon-12,Oxygen-16)
Answer:
129 g of CuO
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
CuCO₃ —> CuO + CO₂
Next, we shall determine the mass of CuCO₃ that decomposed and the mass of CuO produced from the balanced equation. This can be obtained as follow:
Molar mass of CuCO₃ = 64 + 12 + (16×3)
= 64 + 13 + 48
= 124 g/mol
Mass of CuCO₃ from the balanced equation = 1 × 124 = 124 g
Molar mass of CuO = 64 + 16
= 80 g/mol
Mass of CuO from the balanced equation = 1 × 80 = 80 g
SUMMARY:
From the balanced equation above,
124 g of CuCO₃ decomposed to produce 80 g of CuO.
Finally, we shall determine the mass of CuO produced by the decomposition of 200 g of CuCO₃. This can be obtained as follow:
From the balanced equation above,
124 g of CuCO₃ decomposed to produce 80 g of CuO.
Therefore, 200 g of CuCO₃ will decompose to produce
= (200 × 80)/124 = 129 g of CuO.
Thus, 129 g of CuO was obtained from the reaction.
help me pls! plsssss
Answer:
Neutron, neutral subatomic particle that is a constituent of every atomic nucleus except ordinary hydrogen. It has no electric charge and a rest mass equal to 1.67493 × 10−27 kg—marginally greater than that of the proton but nearly 1,839 times greater than that of the electron.
Grease is applied to the moving part of machine.
Answer:
Explanation:
The moving part won't move on its own there's a force but the force isn't enough for something like a bike chain it need grease to move smoothly or else it will just be super stuck or slow.
Answer:
because grease produce more fiction which helps moving part of machine not get jamm while working
as the balloon rises what happens to the external pressure
Answer:
As the ballon rises higher the atmospheric pressure will drop if the ballon is made of an elastic material,it will stretch to allow the gas inside it to expand
A 1.732 g sample of iron is heated in air. It oxidizes to form a product with a mass of 2.205 g.
What is the empirical formula of the product?
Answer:
A 1.732 g sample of iron is heated in air. It oxidizes to form a product with a mass of 2.205 g. What is the empirical formula of the product? FeO 4. Caffeine is made of 49.48% carbon, 5.19% hydrogen, 28.85% nitrogen, and 16.48% oxygen by mass.
Explanation:
The empirical formula of the product formed by the reaction of iron and oxygen is FeO.
Let's consider the following generic chemical equation:
Fe + O₂ ⇄ FexOy
According to the law of conservation of mass, the sum of the masses of the reactants is equal to the sum of the masses of the products. The mass of O₂ that reacted, and remains in the oxide is:
[tex]mFe + mO_2 = mFexOy\\mO_2 = mFexOy - mFe = 2.205 g - 1.732 g = 0.473 g[/tex]
The oxide has 1.732 g of Fe and 0.473 g of oxygen and a total mass of 2.205 g. To determine the empirical formula, we need to calculate the percent composition.
[tex]\%Fe = \frac{mFe}{mFexOy} \times 100 \% = \frac{1.732 g}{2.205 g} \times 100 \% = 78.55\%[/tex]
[tex]\%O = \frac{mO}{mFexOy} \times 100 \% = \frac{0.473 g}{2.205 g} \times 100 \% = 21.45\%[/tex]
Now, we will divide each percentage by the atomic mass of the element.
[tex]Fe: 78.55/55.85 = 1.406\\O: 21.45/16.00 = 1.340[/tex]
Finally, we divide both numbers by the smallest one.
[tex]Fe: 1.406/1.340 \approx 1 \\O: 1.340/1.340 = 1[/tex]
The empirical formula of the product is FeO.
You can learn more about empirical formulas here: https://brainly.com/question/1363167
