Answer:
froth flotation is a technique commonly used in the mining industry. In this technique, particles of interest are physically separated from a liquid phase as a result of differences in the ability of air bubbles to selectively adhere to the surface of the particles, based upon their hydrophobicity.
Explanation:
Froth floatation method is commonly used to concentrate sulphide ore such as galena (PbS), zinc blende (ZnS) etc. (ii) In this method, the metaalic ore particles which are perferentially wetted by oil can be separated from gangue. (iii) In this method, the crushed ore is suspended in water and mixed with frothing agent such as pine oil, eucalyptus oil etc. (iv) A small quantity of sodium ethyl xanthate which act as a collector is also added. (v) A froth is generated by blowing air through this mixture. (vi) The collector molecules attach to the ore particles and make them water repellent. (vii) As a result, ore parrticles, wetted by the oil, rise to the surface along with the froth. (viii) The froth is skimmed off and dried to recover the concentration ore. (ix) The gangue particles that are preferentially wetted by water settle at the bottom.
Answer:A cell is the smallest unit of life, also called the 'building blocks of life' because cells multiply and differentiate to form a multicellular organism as well as give rise to new organism by forming gametes or reproductive spores.
Explanation:
Answer:
-85 °C
Explanation:
O and S are in the same group( Group 16). Since S is below O it's atomic mass is higher than O. So molar mass of H2S is higher than H2O. The strength of Vanderwaal Interactions ( London dispersion forces) increases when the molar mass increases. However, only H2O can form H bonds with each other. This is because electronegativity of O is higher than S and therefore H in H2O has a higher partial positive charge than H of H2S.
H bond dominate among these 2 types of forces so the strength of attractions between molecules is higher in H2O than H2S. Therefore more energy should be supplied for H2O to break inter
molecular forces and convert from solid to liquid state than H2S. So mpt of H2O must be higher than that of H2S.
<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.
