1. a. FeS + 2HCl --> FeCl2 + H2S
b. This is a double- replacement reaction. (The elements "switch partners".)
2. a.2Na + F2 --> 2NaF
b. This is a composition/synthesis reaction. (The two reactants are combining or synthesizing to make one product.)
3. a. 2HgO --> 2Hg + O2
b. This is a decomposition reaction. (The single reactant is breaking down or "decomposing" into multiple reactants.)
4. Hydrogen gas reacts with oxygen gas to create water in a composition/synthesis reaction.
I hope these answers will help you! If you need any explanation, ask and hopefully I can get back to you. ;)
Answer:
0.40 L
Explanation:
Calculation of the moles of
as:-
Mass = 51.24 g
Molar mass of
= 171.34 g/mol
The formula for the calculation of moles is shown below:
Thus,

Volume = 1.20 L
The expression for the molarity is:


Thus,
Considering
Given that:
So,
<u>The volume of 0.24925M stock solution added = 0.40 L
</u>
Answer:
The element that has been oxidized is the N
Explanation:
Zn²⁺(aq) + NH₄⁺(aq) → Zn(s) + NO₃⁻(aq)
See all the oxidation states:
Zn²⁺ → acts with +2
In ammonia, H acts with +1 and N with -3
Zn(s), acts with 0. In all the elements in ground state, the oxidation state is 0.
Zn changed from 2+ to 0. The oxidation number, has decreased.
This element has been reduced.
NO₃⁻ (aq) it's a ion, from nitric acid.
N acts with +5
O acts with -2
The global charge is -1
The N, has increased the oxidation state, so this element is the one oxidized.
<h2>Question no 1:</h2><h2>Answer:</h2>
The correct answer is option A which is Sarah is correct because genetic diversity occurs over a long period of time.
<h3>Explanation:</h3>
- Genetic diversity is a large number of allelic combinations for a trait in specie in a population.
- Genetic diversity is caused due to mutations or random breeding in a specie.
- It is good for the adaptation of specie in an environment, due to diverse in genotypes and phenotype of a trait.
<h2>Question number 2:</h2><h2>Answer:</h2>
The correct answer is option B which is the species will adapt to the changes.
<h3>Explanation:</h3>
- Adaptation to an environment means changing your body in such a way to reduce the harmful affects of changing the environment on the body.
- For example, the long and thick fur of sheeps in a snowy area will protect them from cold.
- If the environment changes, the first thing a specie do is an adaptation to that change in the environment.
<h2>Question 3.</h2><h2>Answer:</h2>
The correct answer is option D which is, "The spines of a cactus protect it from animals".
<h3>Explanation:</h3>
- Adaptation to an environment means changing your body in such a way to reduce the harmful affects of changing the environment on the body.
- For example, the long and thick fur of sheeps in a snowy area will protect them from cold.
- So the plant of cactus was in danger due to animals. So the start growing spines in response to animals.
- Hence the correct answer is option D.
<h2>Question 4.</h2><h2>Answer:</h2>
The correct answer is option B which is, "Marie's plant will lean toward the sun so that it can get the most sunlight".
<h3>Explanation:</h3>
- The plant will lean towards the sun light by the mechanism of phototropism.
- Phototropism is the mechanism of growth of the plant in a specific direction in the response of light.
- There are two types of phototropism.
- One is a positive phototropism in which plant grows towards the light.
- The other is negative phototropism in which plant grows away from the light.
- In this question,the plant will do positive tropism.
<h2>Question no. 5</h2><h2>Answer:</h2>
The correct answer is option B which is, "The dodo bird could not adapt quickly to the challenges of the environment".
<h3>Explanation:</h3>
- Adaptation to an environment means changing your body in such a way to reduce the harmful affects of changing the environment on the body.
- For example, the long and thick fur of sheeps in a snowy area will protect them from cold.
- So the dodo could not adopt to the environment. For the positive adaption of survival, they should be afraid of sailors but the would not afraid of a sailor.
- Due to which they went extinct.
Remaining questions are in attached document.
Answer:
147 amu
Explanation:
CaCl2. 2H2O
=>40*1+35.5*2+2*1*2+2*16
=>40+71+4+32
=>147 amu..
I hope u will understand it:-):-)