另外一題:若把400kg含10%鹽的溶液和600kg含15%鹽的溶液混合,問混合液含鹽百分之幾??(我要知條式係點同答案最好有步驟啦!!)
更新1:
上面果個錯左~!這個才是對的: 一塊重400kg的合金含80%銅和20%錫。若把100kg的銅加入該合金中,問銅佔新合金的百分之幾?(我要知條式係點同答案最好有步驟啦!!)
一塊重400kg的合金含80%錫。若把100kg的銅加入該合金中,問銅佔新合金的百分之幾?
2008-10-02 5:37 pm
一塊重400kg的合金含80%錫。若把100kg的銅加入該合金中,問銅佔新合金的百分之幾?(我要知條式係點同答案最好有步驟啦!!)
另外一題:若把400kg含10%鹽的溶液和600kg含15%鹽的溶液混合,問混合液含鹽百分之幾??(我要知條式係點同答案最好有步驟啦!!)
另外一題:若把400kg含10%鹽的溶液和600kg含15%鹽的溶液混合,問混合液含鹽百分之幾??(我要知條式係點同答案最好有步驟啦!!)
回答 (2)
2008-10-03 12:52 am
哈,一看就知道啦
130 / (400 + 600) x 100%
= 13%
130 / (400 + 600) x 100%
= 13%
2008-10-02 6:29 pm
Q.1
Mass of copper in the original alloy:
= 400 x 80%
320 kg
After the addition of 100 kg copper, the new total mass of the alloy:
= 400 + 100
= 500 kg
Therefore, % of copper in the new alloy:
= (320 + 100 ) / 500 x 100%
= 84%
Q.2
Total mass of salt:
= 400 x 10% + 600 x 15%
= 130 kg
Therefore, final % of salt:
= 130 / (400 + 600) x 100%
= 13%
Mass of copper in the original alloy:
= 400 x 80%
320 kg
After the addition of 100 kg copper, the new total mass of the alloy:
= 400 + 100
= 500 kg
Therefore, % of copper in the new alloy:
= (320 + 100 ) / 500 x 100%
= 84%
Q.2
Total mass of salt:
= 400 x 10% + 600 x 15%
= 130 kg
Therefore, final % of salt:
= 130 / (400 + 600) x 100%
= 13%
收錄日期: 2021-04-24 10:42:27
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081002000051KK00347