kim loại thiếc có nhiệt độ nóng chảy là 232 độ C, thiếc hàn nóng chảy ở khoảng 180 độ C. cho bt thiếc hàn là chất tinh khiết hay có trộn lẫn chất khác nhau? giải thik

What is the main purpose of patent attorneys? defend the company against legal claims manage financial investments invent new products protect rights to new products and processes

Light waves can move through , but they travel fastest when they move through a(n) .

Answer asap need it by wednesday morning carry out the following calculations on ph and ka of from data. i. calculate the ph of 0.02m hcl ii. calculate the ph of 0.036m naoh iii. calculate the ph of 0.36m ca(oh)2 iv. calculate the ph of 0.16m ch3cooh which has ka = 1.74 x 10-5 mol dm-3 v. calculate ka for weak acid ha which has a ph of 3.65 at 0.30m concentration vi. calculate the ka of a solution made by mixing 15.0 cm3 0.2m ha and 60.0 cm3 0.31m a-. [ph= 3.80] vii. calculate the ph of a solution made by mixing 15.0 cm3 0.1m naoh and 35.0 cm3 0.2m hcooh. [ka = 1.82 x 10-4 m]