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An 8.65-g sample of an unknown group 2a metal hydroxide is dissolved in 85.0 ml of water. an acid-base indicator is added and the resulting solution is titrated with 2.50 m hcl(aq) solution. the indicator changes color signaling that the equivalence point has been reached after 56.9 ml of the hydrochloric acid solution has been added.


Answer;

The molar mass of metal hydroxide = 121.66 g/ mole

The formula is Sr(OH)2

Explanation;

M(OH)2 + 2 HCl = MCl2 + 2 H2O  

Moles of the acid = 2.5 x 56.9 / 1000 = 0.14225  

Therefore; moles of hydroxide at the eq point = 0.0711 moles  

These have a mass of 8.65g

Thus; mass of 1 mole = 8.65 / 0.0711

         = 121.66 g / mole  

That means the compound is Sr (OH)2 ..

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The underground depth where rock and sediment are completely saturated with water is referred to as the ________.


~Hello there!

Your question: The underground depth where rock and sediment are completely saturated with water is referred to as the ________.

Your answer: The underground depth where rock and sediment are completely saturated with water is referred to as the water table.

Any queries?

Happy Studying!

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Which of the following would be considered a solution ? A salt in the sugar bowl B sugar added to water C oil added to water D any fat-soluble substance mixed with water soluble substance



Which of the following would be considered a solution ? A salt in the sugar bowl B sugar added to water C oil added to water D any fat-soluble substance mixed with water soluble substance

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Plants return water to the atmosphere through: transpiration perspiration elimination precipitation



Plants return water to the atmosphere through: transpiration perspiration elimination precipitation

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A firefighter stood on the middle rung of a ladder, spraying water on a fire. the smoke lessened, so she moved up 3 rungs. it got too hot, so she backed down 5 rungs. later, she went up 7 rungs and stayed until the fire was out. then, she climbed the remaining 4 rungs and went into the building. how many rungs does the ladder have?



A firefighter stood on the middle rung of a ladder, spraying water on a fire. the smoke lessened, so she moved up 3 rungs. it got too hot, so she backed down 5 rungs. later, she went up 7 rungs and stayed until the fire was out. then, she climbed the remaining 4 rungs and went into the building. how many rungs does the ladder have?

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What kind of change occurs when salt dissolves in water a.) solution change b.) physical change c.) chemical change d.) substance change



What kind of change occurs when salt dissolves in water a.) solution change b.) physical change c.) chemical change d.) substance change

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Which ionic compound is the most likely to dissolve in water? Ba(C2H3O2)2 BaCO3 BaSO4 Ba3(PO4)2



Which ionic compound is the most likely to dissolve in water? Ba(C2H3O2)2 BaCO3 BaSO4 Ba3(PO4)2

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What volume 12.6 M HCL must be added to enough water to prepare 5.00 litters of 3.00 M HCL?


To solve this problem, we shall use the role;
M1V1 = M2V2
M1: is the molarity of the solution before dilution.
V1: is the volume of the solution that we need to dilute.
M2: is the molarity of the solution after dilution.
V2: is the volume of the solution after dilution.

By substitution;
12*V1 = 3*5
V1 = 1.25 litters.

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Why would standing water in tree holes, old tires, buckets and plant trays be especially good places for developing mosquitos?



Why would standing water in tree holes, old tires, buckets and plant trays be especially good places for developing mosquitos?

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A scientist needs to know the temperature of the water every 5 m along 3 km of the river. What tool would the scientist use?



A scientist needs to know the temperature of the water every 5 m along 3 km of the river. What tool would the scientist use?

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You are making flour and water paste. You add 1/4 cup of water to the paste. Your friend adds 1/2 cup of water to the paste. How much water did the two of you add?


Answered by answersmine AT 22/10/2019 – 03:01 AM

3/4 of a cup.If your friend adds a 1/2 a cup of water, that is equivalent to 2/4 as well. if you add the 1/4 cup of water you added to the 2/4 cup of water your friend added you will see that the two of you have added a total of 3/4 of a cup of water to the paste

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In the Earth’s desert biomes, which of the following challenges must be met by animals? A. surviving in a tropical climate B. living with large amounts of rainfall C. surviving in deep jungles and forests D. adapting to droughts and few sources of water



In the Earth’s desert biomes, which of the following challenges must be met by animals? A. surviving in a tropical climate B. living with large amounts of rainfall C. surviving in deep jungles and forests D. adapting to droughts and few sources of water

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In the Earth’s desert biomes, which of the following challenges must be met by animals? A. surviving in a tropical climate B. living with large amounts of rainfall C. surviving in deep jungles and forests D. adapting to droughts and few sources of water



In the Earth’s desert biomes, which of the following challenges must be met by animals? A. surviving in a tropical climate B. living with large amounts of rainfall C. surviving in deep jungles and forests D. adapting to droughts and few sources of water

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Your body is approximately _______ percent water. A. 30 B. 45 C. 60 D. 75



Your body is approximately _______ percent water. A. 30 B. 45 C. 60 D. 75

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Which of these outcomes is conclusive evidence that mixing sugar in water is a physical change



Which of these outcomes is conclusive evidence that mixing sugar in water is a physical change

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A sample of water is mixed with a surfactant what will most likely happen to the viscosity of the water


Answered by answersmine AT 22/10/2019 – 03:15 AM

If a sample o water is mixed with a surfactant, the most likely result is that the viscosity of the water will increase. This is because of the property of the surfactant which is generally viscous; and becomes more viscous when mixed with water. 

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Do you think it is always safe to pour waste chemicals and solution down the sink with lots of water? Explain.


No, it is not always safe to pour waste chemicals and solution down the sink with lots of water because it could be harmful to the environment. When you pour materials down the drain they either enter a septic system or a municipal sewer system. If the material enter a septic system, it goes into a tank buried underground where the solids settle and decompose. The rest of the wastewater is than released into a drain field where it goes into the soil. Sometimes the wastewater kills the good bacteria and can contaminate ground water or surface water.

A municipal sewer system the wastewater goes to a central sewage plant, where after treatment, it is then released into lakes, rivers and streams. Some hazardous household waste can pass through the system unchanged and pollute the waters. Also the wastewater may affect the plumbing or collect in the trap and release fumes through the drains. Most sewage facilities aren’t capable of removing such toxic substances. 

So, No, it is not always safe to pour chemicals and solutions down the sink even with a lot of water.

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How does water move underground?


Answer:

Groundwater is transported through aquifers because of two main reasons: gravity and pressure. In unconfined aquifers, which we concentrate on because they are more likely to be contaminated, water always flows from high points to low points because of gravity.

Explanation:

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A certain skin lotion is a fine mixture of water and various oils. This lotion is cloudy and cannot be separated into oil and water by filtration. Moreover, its components do not separate when left standing. What type of mixture is it? solution suspension colloid compound NextReset


The answer is: colloid.

In the presence of an emulsifying agent, a mixture of oil and water becomes a colloidal dispersion.

Colloidal dispersion (colloid) is a system, in which discrete particles, droplets or bubbles of a dispersed phase (in this case oil), whose size at least in one dimension is in the range from 1 to 1000 nm are distributed in the other, usually continuous phase – dispersion medium (in this case water) differing from the dispersed phase in composition or state of aggregation.

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Match each disease with a hygiene strategy for preventing it. A.Flu Wash your body regularly. B.Athlete's foot Do not share water bottles. C.Salmonella poisoning Cook meat and poultry thoroughly.



Match each disease with a hygiene strategy for preventing it. A.Flu Wash your body regularly. B.Athlete’s foot Do not share water bottles. C.Salmonella poisoning Cook meat and poultry thoroughly.

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Which disease might be prevented by not sharing a water bottle? A.Conjunctivitis B.Cold sores C.Salmonella poisoning D.Athlete’s foot


The following disease might be prevented by not sharing a water bottle: cold sores . Correct answer: B Sharing the same water bottle can lead to catching  diseases or other sicknesses that can be transmitted via saliva.

Infections that can spread via oral transmission are : mononucleosis caused by Epstein-Barr virus (EBV), and cytomegalovirus (CMV), strep throat, the common cold, but also meningitis for example.

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Which Hellenistic inventor and mathematician experimented with levers, created a machine for raising and transporting water and determined formulas for calculating the surface area and volume of a sphere?



Which Hellenistic inventor and mathematician experimented with levers, created a machine for raising and transporting water and determined formulas for calculating the surface area and volume of a sphere?

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In the story “To Build a Fire,” what information did the man ignore? Even though the creeks freeze solid, liquid water exists near springs. Always make camp and build a fire while there is still daylight. Always take along survival gear and wear protective clothing. No one must travel alone in the Klondike after fifty degrees below zero.


Answered by answersmine AT 22/10/2019 – 03:28 AM

No one must travel alone in the Klondike after fifty degrees below zero. I would say this is the main lesson to learn about this Jack London story which shows that nature can be cruel and unforgiving and at 50 degrees below zero it is nothing to fool with. If there are two people, one can help the other and warn say of snow which may fall down and douse the fire and also both can have matches to start a fire and they can discuss the best course of action in any situation which presents itself such as trusting the ice not to break over a creek for example.

Post your answer

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Think about an igneous rock at the top of a mountain. If this rock went through the whole rock cycle, number the steps that would follow. 1. Step 1 Regolith is dumped into some type of reservoir, usually water, by deposition. 2. Step 2 Metamorphic rock begins to melt back into magma. 3. Step 3 Regolith is transported or eroded by rain or wind. 4. Step 4 Rock is broken down into regolith by weathering. 5. Step 5 Layers deposited begin to compact and cement together to form sedimentary rock. 6. Step 6 Sedimentary rock is buried deeper into the earth’s crust. The intense heat and pressure begins metamorphism and the rock turns into metamorphic rock. 7. Step 7 Magma is resurfaced from volcanic activity, cools, and becomes igneous rock.


Answer:

The correct sequence according to the question is steps- 4→1→3→5→6→2→7.

Explanation:

The given steps show that how the rocks are recycled from one form to another form due to certain factors like weathering over geological time scale which was explained by James Hutton and he termed this concept as the rock cycle.

The steps of the rock cycle in sequence according to the question are:

1.  Breakdown of rock by weathering into regolith- step 4

2.  Dumping and deposition of regolith in a reservoir- step  1

3.  Erosion and transportation of regolith by rain or wind- step  3

4. Cementing of the deposited layer to form sedimentary rock- step  5

5. Conversion of sedimentary rock to a metamorphic rock due to intense heat and pressure- step 6

6. Conversion of  metamorphic rocks to magma due to the melting of metamorphic rocks-
step 2

7. Conversion of magma to igneous rocks due to volcanic activities and cooling of magma-  step 7

Therefore sequence according to the question is steps- 4→1→3→5→6→2→7 is correct.

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Water _____. has a pH value of 0 expands when it freezes is less dense than ice dissolves in most substances



Water _____. has a pH value of 0 expands when it freezes is less dense than ice dissolves in most substances