Answer:
Option D is correct.
H₂O + CO₂ → H₂CO₃
Explanation:
First of all we will get to know what law of conservation of mass states.
According to this law, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Example:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
Now we will apply this law to given chemical equations:
A) H₂ + O₂ → H₂O
There are two hydrogen and two oxygen atoms present on left side while on right side only one oxygen and two hydrogen atoms are present so mass in not conserved. This equation not follow the law of conservation of mass.
B) Mg + HCl → H₂ + MgCl₂
In this equation one Mg, one H and one Cl atoms are present on left side while on right side two hydrogen, one Mg and two chlorine atoms are present. This equation also not follow the law of conservation of mass.
C) KClO₃ → KCl + O₂
There are one K, one Cl and three O atoms are present on left side of chemical equation while on right side one K one Cl and two oxygen atoms are present. This equation also not following the law of conservation of mass.
D) H₂O + CO₂ → H₂CO₃
There are two hydrogen, one carbon and three oxygen atoms are present on both side of equation thus, mass remain conserved. Thus is correct option.
Answer:
<u>The consequences of soil erosion</u> go beyond the loss of fertile land. It has contributed to increased runoff and sedimentation in streams and rivers, clogging these waters and causing declines in fish and other animals.
We can protect the community from soil erosion by -:
- Maintaining a good, perennial cover for plants.
- Planting a crop for cover
Explanation:
<u>SOIL EROSION -:</u> The soil erosion mechanism is both natural and man-made. In nature, this refers to the removal of the top layer of soil caused by wind and water, while human activity may increase exposure to these elements.
<u>MAJOR EFFECTS OF SOIL EROSION -:</u>
- <u>Pollution and Low Water Quality -:</u> Sedimentation is created by gradual soil erosion, a process by which rocks and minerals in the soil are separated from the soil and deposited elsewhere, often in streams and rivers. Soil contaminants, such as fertilizers and pest control agents, often settle in the streams and rivers to protect crops. Water contaminants contribute to low water quality, including drinking water quality, if the contaminants are not removed prior to ingestion. As sunlight can get through the sediment, sedimentation also leads to the excessive growth of algae. According to the World Wildlife Fund, high levels of algae drain too much oxygen from the water, resulting in the mortality of marine species and reduced fish stocks.
- <u>Structural Issues and Mudslides -:</u> Soil erosion contributes to mudslides, impacting the stability of buildings and roadways and their structural integrity. Mudslides affect not only soil-supported structures, but also buildings and roads that are in the path of slides. Mudslides occur when, as a result of the intensity and energy of heavy rainfall, fine sand , clay, silt, organic matter and soil spill off the sides of hills and slopes. According to Envirothon, a program of the National Conservation Foundation and North America's largest high school environmental education competition, this runoff happens rapidly, because there is not enough time for the surface to reabsorb or catch the eroding soil.
- <u>Flooding and Deforestation -:</u> Deforestation erodes soil — the removal of trees to create space for towns and agriculture. Trees help to maintain soil in place, so winds and rains drive the loose soil and rocks to streams and rivers when they are uprooted, resulting again in unnecessary sedimentation. The thick layers of sediment keep streams and rivers from flowing smoothly, ultimately contributing to flooding. Excess water, especially during rainy seasons and when the snow melts, gets trapped by the sediment and has nowhere to go except back on land.
- <u>The Deterioration of Soil -:</u> Soil nutrient depletion is often the result of poorly performed cultivation and cultivation practices that contribute to soil erosion. For natural vegetation and agricultural purposes, excessive irrigation and obsolete tilling practices decrease the amount of nutrients in the soil and make it less fertile.
<u>PROTECTION OF COMMUNITY FROM SOIL EROSION -</u>
- <u>Maintaining a good, perennial cover for plants -:</u> Your perennial garden's care and upkeep need not be difficult or overwhelming. A blend of certain simple horticultural values with common sense and a good eye is a great part of good gardening.
- <u>MULCHING -:</u> The amount of water that evaporates from your soil will be reduced by mulch, greatly reducing the need to water the plants. By breaking up clay and permitting better movement of water and air through the soil. Mulch supplements sandy soil with nutrients and enhances its ability to retain water.
- <u>PLANTING A CROP FOR COVER -: </u> Winter rye in vegetable gardens, for instance. This includes annual grasses, small grains , legumes and other forms of vegetation that have been planted to provide temporary vegetative cover. Cover crops are also often tilled as a 'green manure' crop under serving.
Answer: 53.3
Explanation:
V2=(T2 x P1 x V1)/(T1 x P2)
(320x50x80)/(300x80)
53.3
Answer:
Explanation:
Heat lost by metal = mass x specific heat x fall in temperature
= 74 x S x ( 94 - 32 )
= 4588 S
heat gained by water = mass x specific heat x rise in temperature
= 120 x 1 x ( 32 - 26.5 ) ( specific heat of water is 1 cals / gm )
= 660
Heat lost = heat gained
4588S = 660
S = .14 cal /gm .
Specific heat of metal = .14 cal / gm