This lesson is the first in a three-part series that addresses a concept that is central to the understanding of the water cycle—that water is able to take many forms but is still water. This series of lessons is designed to prepare students to understand that most substances may exist as solids, liquids, or gases depending on the temperature, pressure, and nature of that substance. This knowledge is critical to understanding that water in our world is constantly cycling as a solid, liquid, or gas.
In these lessons, students will observe, measure, and describe water as it changes state. It is important to note that students at this level "...should become familiar with the freezing of water and melting of ice (with no change in weight), the disappearance of wetness into the air, and the appearance of water on cold surfaces. Evaporation and condensation will mean nothing different from disappearance and appearance, perhaps for several years, until students begin to understand that the evaporated water is still present in the form of invisibly small molecules." (Benchmarks for Science Literacy<span>, </span>pp. 66-67.)
In this lesson, students explore how water can change from a solid to a liquid and then back again.
<span>In </span>Water 2: Disappearing Water, students will focus on the concept that water can go back and forth from one form to another and the amount of water will remain the same.
Water 3: Melting and Freezing<span> allows students to investigate what happens to the amount of different substances as they change from a solid to a liquid or a liquid to a solid.</span>
The other students in the lab should be notified next in this type of scenario.
<h3>What is an acid?</h3>
This is a substance which donates protons and is very corrosive. It also turns blue litmus paper red.
When it was spilled and baking soda was used to neutralize it on the floor , it is best to inform the other students too so as to prevent them from being exposed by mistake thereby reducing risk of injury.
Read more about Acid here brainly.com/question/25148363
#SPJ1
It shows that the population is moving towards a more organic and natural way of growing crops. Rather than using fertilizer and putting toxins on the plants that we eat from, we are getting smarter and growing food naturally. Thus not killing ourselves in the process.
Answer:
Explanation:
Efficiency of the electric power plant is 
Here Temperature of hot source 
and Temperature of sink 
Hence the efficiency is 
Now another formula for thermal efficiency Is
Here QI is the of heat taken from source 100 MJ ; Q2 of heat transferred to the sink (river) to be found
W is the of work done and W = QI -Q2
Hence From
Hence the of heat transferred to the river Is 
Answer:
<h2>mass = 200.23 g</h2>
Explanation:
The density of a substance can be found by using the formula
Since we are finding the mass
<h3>mass = Density × volume</h3>
From the question
Density = 0.81 g/mL
volume = 247.2 mL
Substitute the values into the above formula and solve for the mass
mass = 0.81 × 247.2
= 200.232
We have the final answer as
<h3>mass = 200.23 g to 2 decimal places</h3>
Hope this helps you
