소금과 모래의 분별 결정화

용해도 차이를 이용해 혼합물 분리하기

Crystallization Beginner (Middle School) 35 분 ~$3.00

목표

소금과 모래의 혼합물을 분별 결정화로 분리하고, 용해·여과·증발 결정화를 실증한다.

배경

This classic separation technique exploits the fact that salt dissolves in water while sand does not. The mixture is dissolved in hot water, filtered to remove sand, and then the salt is recovered by evaporation. This is fundamentally how salt has been harvested from seawater for millennia.

안전 경고

  • Handle hot evaporating dish with tongs
  • Do not heat to dryness too rapidly — spattering risk

필수 개인 보호 장비

goggles

재료

  • Salt-sand mixture (10 g)
    Pre-mixed approximately 50:50
  • Distilled water (100 mL)

장비

250 mL beaker Filter paper Funnel Evaporating dish Hot plate Stirring rod Analytical balance

실험 절차

1

Weigh 10 g of the salt-sand mixture and record the mass.

2 분
2

Add the mixture to 100 mL of warm water in the beaker. Stir for 5 minutes to dissolve all the salt.

5 분
3

Filter the mixture through filter paper. The sand remains on the filter; the salt solution passes through.

5 분
4

Rinse the sand on the filter with a small amount of distilled water. Dry the sand and weigh it.

5 분
5

Pour the filtrate into the evaporating dish. Heat gently on the hot plate to evaporate the water.

12 분 Remove from heat before completely dry
6

Once dry, weigh the recovered salt. Calculate the percentage of each component.

3 분
7

Compare the total recovered mass with the initial mass. Calculate percent recovery.

3 분

예상 결과

The total mass of recovered salt + sand should be close to the original 10 g (typically 90-98% recovery). Some loss occurs during transfer and on filter paper. The separated components should be visually distinct.

정리

Salt solution can go down the drain. Sand can go in the trash. Rinse all glassware.

세부 정보

카테고리
Crystallization
난이도
Beginner (Middle School)
소요 시간
35 분
예상 비용
$3.00
단계
7
재료
2

더 많은 실험

비스무트 무지개빛 결정 키우기 45 min 안식향산 재결정 정제 45 min 과포화와 순간 결정화 35 min 황산구리 결정 키우기 30 min 명반 결정 키우기 30 min 설탕 결정(락캔디) 25 min 살롤(살리실산페닐) 결정화 30 min

Frequently Asked Questions

What is the objective of 소금과 모래의 분별 결정화?
소금과 모래의 혼합물을 분별 결정화로 분리하고, 용해·여과·증발 결정화를 실증한다.
How difficult is 소금과 모래의 분별 결정화?
This experiment is rated as Beginner (Middle School). It takes approximately 35 minutes to complete.
What safety precautions are needed for 소금과 모래의 분별 결정화?
Key safety precautions include: Handle hot evaporating dish with tongs; Do not heat to dryness too rapidly — spattering risk.
What materials are needed for 소금과 모래의 분별 결정화?
The main materials required are: Salt-sand mixture, Distilled water.
What results should I expect from 소금과 모래의 분별 결정화?
The total mass of recovered salt + sand should be close to the original 10 g (typically 90-98% recovery). Some loss occurs during transfer and on filter paper. The separated components should be visually distinct.