【简答题】(8分)按要求写出298K、101 kPa时下列反应的热化学方程式: (1)3mol NO 2 (g)与1 mol H 2 O(1)反应生成HNO 3 (aq)和NO(g),放热138kJ:____________。 (2)1 mol HgO(s)分解为液态汞和氧气,吸热90.7kJ:___________________。 (3)①下图是一定量丙烷完全燃烧生成CO 2 和1 mol H 2 O(...
【单选题】The local government supplied the poor children _______free text-books and some companies supplied food __________ them.
【简答题】Case 2 Importance of Pre-negotiation Preparation Some Chinese companies ignore the importance of collecting necessary information and doing investigation on their trading partners' financial position ...
【单选题】犬 牙齿的 保养很重要 , 以下 关于 犬 牙齿 保养 的 叙述正确 的是 ( )。
A.
犬 的换牙期为了让 犬 能长出坚硬的牙齿,应该让它多啃 骨头 。
B.
犬 应该刷牙,对于无法接受刷牙的 犬 应该喂些狗咬胶或是 骨头 之类的洁牙食品。
C.
为了保护 犬 的牙齿,应该尽量给 犬 弄一些软的或是好嚼的食品。
【简答题】已知反应 NH 4 NO 3 (s) N 2 O(g) + 2H 2 O(l) 298 K 时, NH 4 NO 3 (s) N 2 O(g) H 2 O(l) / kJ·mol -1 -365.56 81.55 -285.85 / J·mol -1 ·K -1 151.08 219.99 69.96 (1) 反应是吸热还是放热? (2) 在 298 K , 是多少? (3) 等于多少? (4) ...
【单选题】What did some logging companies do?
A.
They gave local communities $100,000.
B.
They did not keep promises to local communities.
C.
They offered local communities precious gifts.
D.
They fought with local communities.
【单选题】Local _________ companies say some homes won't be reconnected until the end of the week.
【单选题】Some US companies have understood the need to win the confidence of local customers. _____
【多选题】FM可以采用增加下列哪种参数来改变其抗噪声性能?