Dẫn H2 đến dư đi qua 25,6gam hỗn hợp X gồm Fe304,MgO, CuO(nung nóng) cho đến khi phản ứng hoàn toàn xảy ra. Sau phản ứng thu được 20,8gam chất rắn . mặt khác 0,15 mol hỗn hợp X tác dụng vừa đủ với 225ml dung dịch HCl 2.0M a. Viết ptpứ xảy ra
b. Tính % số mol các chất trong hỗn hợp X

Construct the hypothetical phase diagram for metals a and b between room temperature (20c) and 700c, given the following information: * the melting temperature of metal a is 480c. • the maximum solubility of b in a is 4 wt% b, which occurs at 420c. • the solubility of b in a at room temperature is 0 wt% b. • one eutectic occurs at 420c and 18 wt% b–82 wt% a. • a second eutectic occurs at 475c and 42 wt% b–58 wt% a. • the intermetallic compound ab exists at a composition of 30 wt% b–70 wt% a, and melts congruently at 525c.• the melting temperature of metal b is 600c. • the maximum solubility of a in b is 13 wt% a, which occurs at 475c. • the solubility of a in b at room temperature is 3 wt% a.

Aside from human impact, which of the following causes less water vapor production over a small area? (2 pderivartin

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.