Answer:
B. CaCl₂ + H₂CO₃ → CaCO₃ + 2HC
Explanation:
A balanced reaction has the same number of atoms in the both sides of the reaction. In the options:
A. CaCl₂ + H₂CO₃ → 2CaCO₃ + HCI
In this reaction there is 1 Ca in reactants and 2 in products -<em>The reaction is unbalanced-</em>
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<h3>B. CaCl₂ + H₂CO₃ → CaCO₃ + 2HCl
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There is 1 Ca is both sides, 2Cl, 2H, 1C and 3 Oxygens -<em>The reaction is balanced</em>
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C. CaCl₂ + 2H₂CO₃ → CaCO₃ + HCI
There is 1 Ca in both sides but 2Cl in reactants and 1 in Cl -<em>The reaction is unbalanced-</em>
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D. 2CaCl₂ + H₂CO₃ →CaCO₃ + HCI
There are 2 Ca in reactants and 1 in Ca -<em>The reaction is unbalanced-</em>
Answer:
(i) Oxidizing Agent: NO2 / Reducing Agent NH3-
(ii) Oxidizing Agent AgNO3 / Reducing Agent Zn
Explanation:
(i) 8NH3( g) + 6NO2( g) => 7N2( g) + 12H2O( l)
In this reaction, both two reactants contain nitrogen with a different oxidation number and produce only one product which contains nitrogen with a unique oxidation state. So, nitrogen is oxidized and reduced in the same reaction.
Nitrogen Undergoes a change in oxidation state from 4+ in NO2 to 0 in N2. It is reduced because it gains electrons (decrease its oxidation state). NO2 is the oxidizing agent (electron acceptor).
Nitrogen Changes from an oxidation state of 3- in NH3 to 0 in N2. It is oxidized because it loses electrons (increase its oxidation state). NH3 is the reducing agent (electron donor)
(ii) Zn(s) +AgNO3(aq) => Zn(NO3)2(aq) + Ag(s)
Ag changes oxidation state from 1+ to 0 in Ag(s).
Ag is reduced because it gains electrons and for this reason and AgNO3 is the oxidizing agent (electron acceptor)
Zn Changes from an oxidation state of 0 in Zn(s) to 2+ in Zn(NO3)2. It is oxidized and for this reason Zn is the reducing agent (electron donor).
Balanced equation:
Zn(s) +2AgNO3(aq) => Zn(NO3)2(aq) + 2Ag(s)
Answer:
Human activity is by far the biggest cause of habitat loss.
Humans are now responsible for causing changes in the environment that hurt animals and plant species. We take up more space on Earth for our homes and cities. We pollute habitats. ... Human activity often changes or destroys the habitats that plants and animals need to survive.
Explanation:
Human activities are the various actions for recreation, living, or necessity done by people. For instance it includes leisure, entertainment, industry, recreation, war, and exercise.
Over time, destruction of such habitats leads to reduced biodiversity, weakening the Earth's ecosystems, and ultimately posing a major threat to human life. While, significant tracts of habitat have been lost, and along with them many species of plant and animal, steps can be taken to slow and even reverse the process.
One of the most significant ways in which humans have impacted on the lives of other species is by causing climate change. Many animals, including birds and frogs, now breed much earlier in spring in Britain than they did 20 years ago. Whether or not this is having a harmful effect on them has yet to be determined.
To solve this problem, we use Beer's Law: A= ε.l.c
A is the absorbance- 0,558
<span>ε is</span> the molar absorptivity- is <span>15000 </span><span><span>L⋅mol-1</span><span>cm-1</span></span>
<span>l is </span>the length of the cuvette- 1 cm
<span>c is</span> the molar concentration
Applying the formula,
0,558= 15000 x 1 x c
0,558/15000= c
c= <span>3.72×<span>10⁻⁵ </span> <span>mol⋅L<span>⁻¹</span></span></span>
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