求解 謝謝

The figure shows a three-particle system, with masses mu = 4.2 kg. m2 = 2.8 kg, and m2 = 7.3 kg. What are (a) the x coordinate and (b) the y coordinate of the system's center of mass? 13 2 1 x (m)

《普通化學》第九題跟第十題，感恩。

Alinie 2 PBurel H12 lapf Setul lagly x2 e determined by titfátinga 100 sample of KCror. Nos cag & beth 14 raqla 1: 191 +24100) No. (aq) + 2 Al Al EX Mn of laql4 2 1 7 Mn Oz (s) + Al(Orta 9. The blood alcohol (C2H5OH) level can be potassium dichromate solution, resulting in the production of Cr3+ (aq) and carbon dioxide. The reaction can of blood plasma with an acidic be monitored because the dichromate ion. (Cr20,?) is orange in solution, and the Cr" ion is green. The unbalanced redox equation is C₂H5OH(aq) + 3H₃0 (aq) + 2 CO2 (g) +12Hg) Me Cr2O,?- (aq) + CHșOH (aq) --Cr"(aq) + CO2(8) 14 Heag toe Cruon Lafla203149) If 31.05 mL of 0,0600_M potassium dichromate solution is required to titrate 30.0 g of blood plasma, Hamm Fapter (aq) determine the mass percent of alcohol in the blood. 0.143% Ca H5OH. 2- tize 32.0 g 10. An average human being has about 5.0 L of blood in his or her body. If an average person were to eat ht of sugar (sucrose, C12H22011, 342.30 g/mol), and all that sugar were dissolved into the bloodstream, how would the molarity of the blood sugar change? HO +1 HO +1 H &H to H - 31 OH HO HIP 126 0 HO +1 + 5e OH OH OH (+36 ) x2 t6 Cr2O7 - 20+ 3+

請教一下，我今天做到一個實驗是酸鹼滴定實驗，但我忘了圖上要的酸度與鹼度的定義是甚麼？我覺得我的數據有點奇怪，正常來說，算％會到124％嗎？

万粉 度(%) 酚酞指示劑 滴 ·食醋的酸度測定 1009.49 . 5 b 6 soo 1. 1ooo CH 0.0012 x16Q、 0,12%. 1008 -x100 CH3COOH 1000 X 100 CH3COOH(ml) 20 0.6 the = 12 % 氫氧化鈉(NaOH) 食醋 甲基橙 實驗步驟 to = 4 1000 40.9 too 29 取一乾淨5ml 刻度吸量管,精確吸取 5ml 的食醋於250ml 錐形瓶內,加入約100ml 的純水,使 49 起充分溶解,再加5滴酚酞指示劑(溶液為無色)。 已知濃度 0.1N 的NaOH 的標準溶液滴定至溶液成粉紅色為止。 3. 假設食醋的比重是1.00,依下式計算食醋的酸度: 0-1 x Nox NbxV 酸度(%)= 3 4. 重複實驗一次,求出食醋中的酸度平均值(%) - 二、去污粉鹼度測定 1. 稱取約0.25g的家庭用去污粉倒入250ml 錐形瓶內,加入約100ml 的溫水,使起充分溶解,冷 卻後再滴5滴甲基橙。 vol 2. 已知濃度 0.1N 的 HC1 的標準溶液滴定至溶液成橙色為止。 (600 3. 依下式計算去污粉的酸度(Na2O計): 36.5 NaxVa> 鹼度(%)-- X 100 [00 3.65 x2 Na2O(g) 4. 重複實驗一次,求出去污粉中的鹼度平均值(%) 200 7.30 slxy F1 249)) 62 3lio.25 NX Too x Toro | Na20 2000 32 al XIX 29 Xyup.

水文學——降水與損失 如圖，請問有人知道這兩題該怎麼算嗎？ 翻遍教科書教過的內容根本沒想法⋯

> 0 2-14 有一矩形集水區,其四個角落的座標分別為(0,0),(0,10), (14,10) 和 (14,0)。集水區內設有四個雨雨量測站,各測站所在位置的座標及降雨量如下 表。所有座標值的單位均為公里。試以徐昇氏法推算此集水區的平均降雨量 及逕流總體積(註:假設無任何降雨損失) o 雨量站位更 (4,2) (4,7) (11 , 7) | (11,2) 降雨量(cm) 1.5 2.0 2.4 4.3 ( 86 水利工程簡任升等)

求解 答案1/6

Go Figure Estimate the fraction of molecules at 100 °C with speeds less than 300 m/s. Ump At 0 °C, fewer than half the molecules move at speeds greater than 500 m/s. At 100 °C, more than half the molecules move at speeds greater than 500 m/s. the speed exhibited by the largest number of molecules Uav = the average (mean) speed of all the molecules Urms the speed of a molecule whose kinetic energy is equal to the average (mean) kinetic energy of all the molecules 0 °C 100 °C | || Fraction of molecules Fraction of molecules | || 11 1 |||| 11 0 0 5 X 102 10 X 102 Molecular speed (m/s) (a) 5 X 102 10 X 102 Molecular speed (m/s) (b)

有人知道我是哪裡算錯嗎(ಥ_ಥ)

= 78, When the electron in a hydrogen atom falls from the n= 3 excited energy level to the ground state energy level, a photon with wavelength 2 is emitted. An electron having x this same wavelength would have a velocity of A) 7.10 x 10 m/s. D) B) 2.93 x 10 m/s. E) C) 2.93 x 103 m/s. Ans: A Category: Medium Section: 7.4 7.10 m/s. 3.00 x 108 m/s.

求解 謝謝

20 電路學精析 \\\ D 2:02 2A 2y 12 7A 2A \\\< 292 42 7A C (b) (a) 202 3.10 應用:(a) KCL 到超節點,(b) KVL到迴路 練習題3.3 試求圖3.11 電路的,和i。 題 求和io 11 492 6V 3.13 三 答:-400 mV, 2.8A. 14 V + 392 -\\\\ 1 + 在節點35 江 202 一八八一 VW 60 3.11 練習題3.3 的電路 或 4,試求圖3.12 電路的節點電壓。 接下來形 32 ANA-

請問這題有效數字 是怎麼知道是三個的... 想知道過程

F = $x7.02+32 = 12,636+32 二 6

求解

Using Heisenberg's uncertainty principle, calculate the uncer- tainty in the position of (a) a 1.50-mg mosquito moving at a speed of 1.40 m/s if the speed is known to within +0.01 m/s; (b) a proton moving at a speed of (5.00 + 0.01) x 104 m/s. (The mass of a proton is given in the table of fundamental constants in the inside cover of the text.)

求算法

CD 0 2. - 女用 has p5 Ca,样品。第去耳其东化 p出Ai质,取 2.8 m+牛的博 BOTTE, 4 x 2 = 7 13 2 1 12 m& INHCl, 1 t = 70 22 X 1 NHCl 2 2 2 450 ml 2# - 5, [123 + 1 = 72 = 3 m 2 , too 13 ml in HCl 477 $1 to 2 0.5 ml Et tě 60 70 22 76 0.5ml 17 18 %0 (10-100 ppm (a) ux AAST IT CA 5 2 1 5 EUR 7 2 7 7 6 28.2 ppm Ca , & 10) * 3 2 2 4 4 43 ob ca 5 2 2 x ppm & & TE?