Why is mass conserved in
chemical reactions?

Answers

Answer 1

Answer: Even in a chemical reaction when atoms interact and create new products, mass is conserved. This is because the new substances created are composed of atoms that were present in the reactants. ... No new atoms have entered or left the system so the mass is conserved.

Related Questions

Natural gas, or methane, is an important fuel. Combustion of one mole of methane releases 802.3 kilojoules of energy. How much energy does that represent in kilocalories?
How would you physical separate ? A.) NaCl solution B.) sand & water C.) Italian salad dressing
The sum of the potential energy and the kinetic energy of an object is its thermal energy. True or false?
If salt is dissolved in water, water serves as the:a. solute.b. solvent.c. dissolved medium.d. none of the above
Calculate the change of enthalpy for the reaction CH4 (g) + NH3 (g) --> HCN (g) +3H2 (g) from the following reactions: Reaction 1: N2 (g) + 3H2 (g) --> 2NH3 (g) Change in enthalpy: -91.8 kJ/molReaction 2: C (s, graphite) + 2H2 (g) --> CH4 (g) Change in enthalply: -74.9 kJ/molReaction 3: H2 (g) + 2C (s, graphite) + N2 (g) --> 2HCN (g) Change in enthalpy: +270.3 kJ/molInclude the following:The numerical answer with correct units.State which reactions, if any, you had to "Flip".State which reactions you had to multiply, if any, to get the correct amount of the compound.

1.94 grams of magnesium to moles

Answers

Answer:

0.0798 mol Mg

Explanation:

a) divide the number of grams of magnesium by the molar mass of magnesium found on the periodic table

1.94g Mg/(24.31g Mg/mol Mg)=0.0798 mol Mg

What is a Benedict solution?

Answers

Benedict's solution, deep-blue alkaline solution used to test for the presence of the aldehyde functional group, - CHO. The substance to be tested is heated with Benedict's solution; formation of a brick-red precipitate indicates presence of the aldehyde group. Since simple sugars (e.g., glucose) give a positive test, the solution is used to test for the presence of glucose in urine, a symptom of diabetes. One liter of Benedict's solution contains 173 grams sodium citrate, 100 grams sodium carbonate, and 17.3 grams cupric sulfate pentahydrate. It reacts chemically like Fehling's solution; the cupric ion (complexed with citrate ions) is reduced to cuprous ion by the aldehyde group (which is oxidized), and precipitates as cuprous oxide, Cu2O

A magnifying glass is an example of a _______ lens.a. plano-convex
b. plano-concave
c. converging
d. double-concave

Answers

there are two types
1) plano convex
2)doule convex

so the answer is-----(c)

a. plano-convex
b. plano-concave
c. converging <-------------------
d. double-concave

Unrestricted populations of organisms experience _____.a. exponential growth
b. linear growth
c. fertility
d. biotic growth
User: As a population reaches its carrying capacity, there is an increase in competition for
a. food.
b. shelter.
c. mates.
d. All of the above

Answers

Answer:

1. A

2. D

Explanation:

1. If a population is left unrestricted, meaning it is not limited to anything, then the population will continue to increase exponentially due to there being no limits.

2. If a population is limited, and it has reached its carrying capacity, then the essential needs of life are being competed for. Things like food, shelter, and mates are now a limited resource, and hence the option would be "all of the above".

Unrestricted populations of organisms experience Exponential growth.

As a population reaches is carrying capacity there is an increase in competition for All of the above.
Hope I helped.

Which change is exothermic?(1) freezing of water(2) melting of iron(3) vaporization of ethanol(4) sublimation of iodine

Answers

The answer is (1) freezing of water. The energy of different status is increase from solid to liquid to gas. So the change of liquid to solid is exothermic. The other three are endothermic.

Consider the solutions, 0.04 m urea [(NH2)2C=O)], 0.04 m AgNO3 and 0.04 m CaCl2. Which has (i) the highest osmotic pressure, (ii) the lowest vapor pressure, (iii) the highest boiling point?

Answers

Answer:

i) Highest osmotic pressure: CaCl2

ii) lower vapor pressure : CaCl2

iii) highest boiling point : CaCl2

Explanation:

The colligative properties depend upon the number of solute particles in a solution.

The following four are the colligative properties:

a) osmotic pressure : more the concentration of the solute, more the osmotic pressure

b) vapor pressure: more the concentration of the solute, lesser the vapor pressure.

c) elevation in boiling point: more the concentration of the solute, more the boiling point.

d) depression in freezing point: more the concentration of the solute, lesser the freezing point.

the number of particle produced by urea = 1

the number of particle produced by AgNO3 = 2

the number of particle produced by CaCl2 = 3

As concentrations are same, CaCl2 will have more number of solute particles and urea will have least

i) Highest osmotic pressure: CaCl2

ii) lower vapor pressure : CaCl2

iii) highest boiling point : CaCl2

Final answer:

The solution with the highest number of particles in solution (CaCl2 in this case), experiences the highest osmotic pressure, lowest vapor pressure and highest boiling point due to the principles of colligative properties.

Explanation:

The question pertains to the colligative properties of solutions, which would be governed by the number of particles in the solution. The solutions are 0.04 m urea [(NH2)2C=O)], 0.04 m AgNO3, and 0.04 m CaCl2. For (i) Highest osmotic pressure, the solution with the highest ion count would yield the highest osmotic pressure. CaCl2 dissociates into three ions (Ca²+, and 2 Cl¯), therefore, it would exhibit the highest osmotic pressure. For (ii) Lowest vapor pressure, this would coincide with the solution with the highest osmotic pressure, again making it CaCl2, due to the greatest decrease in vapor pressure. For (iii) the highest boiling point, this too would be CaCl2 for the reasons stated above. The presence of more particles in a solution interferes more with the evaporation process, requiring more energy (higher temperature) to achieve boiling.