"Changes of Candles" PPT

Description

"Changes of Candles" PPT

Part One: Studying Candles

A study that begins with observing candles

1. What are the characteristics of candles if you carefully observe them?

(Can be ignited, cut, brittle, hard, smooth-------)

2. If you want to make candles change, what methods would you use?

Heating, lighting, cutting

Take a look at what materials the teacher has prepared for you on the table, and what are their uses? How will you use these materials to conduct experiments? Discuss as a group:

Experimental requirements:

1. Complete the experiment according to the method just discussed in the group, paying attention to the cooperation between group members.

2. Before the experiment, make a guess: What phenomena will occur in the experiment?

3. Pay attention during the experiment: the team leader divides the work well and maintains the discipline of the group. Everyone carefully observes the phenomenon of the experiment, fills in the experiment report carefully, and the recorder takes notes carefully.

Changes in Candles PPT, Part 2: Experiment

(1) Experiment of "heating candles":

Experimental steps for heating candles:

(1). Place the small piece of candle in the evaporating dish.

(2) Light the alcohol lamp and use the alcohol lamp to heat the iron stand for a few minutes to see the changes in the candle.

(3) Extinguish the alcohol lamp (use the alcohol lamp cover to extinguish the alcohol lamp), then remove the evaporating dish with a clip, place it on hard paper, and wait for the wax oil to cool down to see what it looks like?

(2) Experiment of "lighting the candle":

Experimental steps for "lighting the candle":

(1) Use a match to light a candle and see what happens to the candle?

(2) When lighting a candle, black smoke is produced on the flame. In order to clearly see what the black smoke looks like? You can use a clamp to place the glass piece about 1-2 cm above the candle flame and observe what happens on the glass piece?

Changes in Candles PPT, Part 3: Summary

Candle lighting-----new substances are produced after the candle burns

Chemical changes

Heating the candle -----The candle melts into wax oil--then solidifies into wax block after cooling, no new substances are produced

physical changes

Changes in Candles PPT, Part 4: Substance Classification

Through the experiment just now, we know what types of changes in matter are divided into?

Changes in matter can be divided into two major categories: one is just a change in form, without producing new substances, such as a candle melting when heated; the other is a change that produces new substances, which can often start with a change in color, precipitation or Bubbles, luminous heat and other phenomena are manifested, such as the burning of candles.

Heating Candles: Physical Changes

Under the influence of temperature, the candle changes from solid to liquid. No new substance is produced, so it is a physical change.

Lighting a candle: both physical and chemical changes

During the burning process: the temperature is also rising, and wax oil is dripping (physical change)

Water, carbon dioxide, carbon black, etc. are produced (chemical changes)

Changes in Candles PPT, Part 5: Practice

1. Determine whether the following changes are physical changes or chemical changes

⑴ Grind the iron block into iron powder

⑵Put the iron block on the ground and it will rust.

⑶Put the wet clothes in the sun and dry them

⑷Pull copper ingots into copper wire

⑸Iron melts into molten iron at high temperature

⑹Burning of coal

2. Determine whether the following changes are physical changes or chemical changes

⑴Air liquefaction

⑵ Bronze becomes green and rusty

⑶Carbon dioxide turns clear limewater turbid

⑷Alcohol evaporates

⑸Gunpowder explosion

⑹The filament emits light and releases heat after being energized.

Changes in Candles PPT, Part Six: The Connection and Difference between Physical Changes and Chemical Changes

1. The fundamental difference between the two:

Are there any new substances generated during the change?

2. The connection between the two:

Chemical changes must be accompanied by physical changes

Physical changes are not necessarily accompanied by chemical changes

Keywords: Free download of Qingdao version of fifth grade science PPT courseware, Volume 1, Changes of Candles PPT download, .PPT format;

For more information about the "Changes of Candles" PPT courseware, please click the "Changes of Candles" ppt tab.

"Changes of Candles" PPT courseware:

"Changes of Candles" PPT courseware Part One: Observing Candles Research starting from observing candles 1. What are the characteristics of candles if you carefully observe them? 2. If you want to make candles change, what methods would you use? Experimental Journey Warm Tips 1. Use a knife to cut...

File Info

Update Time: 2024-07-02

This template belongs to science courseware Qingdao Edition Fifth Grade Science Volume 1 industry PPT template

Preview