Questions in Grade High-school

Questions in Grade High-school

[Done] The equation below represents a reaction that takes place in an industrial process. [tex]4NH_3 + 5O_2 \rightarrow 6H_2O + 4NO[/tex] a. Name the catalyst used. b. What are the other conditions for the reaction? c. Why are the products cooled before being oxidized?

[Done] If the set of all a ∈ ℝ, for which the equation 3x² + (a - 6)x + (5/4)a = 3 has no real root, is the interval (α, β) and X = {x ∈ ℤ; α < x < β}, then \(\sum_{x \in X} x^2\) is equal to:

[Done] Round off to the nearest 10: a) 22 -> 20 b) 35 -> 40 c) 48 -> 50 d) 65 -> 70 e) 72 -> 70 f) 83 -> 80 g) 191 -> 190 h) 348 -> 350 i) 4508 -> 4510 j) 612 -> 610 k) 5421 -> 5420

[Done] An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?

[Done] Why did Mendeleev reverse the order of the tellurium (Te) and iodine (I) elements?

[Done] Select the correct answer. Which statement correctly relates two substances from this reaction? [tex]H_2 CO_3+H_2 O \rightleftharpoons H_3 O^{+}+HCO_3^{-}[/tex] A. [tex]HCO _3{ }^{-}[/tex] is the conjugate acid of [tex]H _2 CO _3[/tex]. B. [tex]H _2 O[/tex] is the conjugate base of [tex]H _2 CO _3[/tex]. C. [tex]H _3 O ^{+}[/tex] is the conjugate acid of [tex]H _2 O[/tex]. D. [tex]H _2 CO _3[/tex] is the conjugate base of [tex]H _3 O ^{+}[/tex].

[Done] Which best describes the Iran-Contra Affair? A. US military build-up B. a fight against terrorists C. a secret diplomatic effort D. a secret arms deal

[Done] Solve the inequality and graph the solution set. $\frac{x+9}{x-4}>0$

[Done] What is the difference between the place values of 8 and 5 in the number 428356?

[Done] Siera calculated her home town's average high temperature in degrees Fahrenheit. She wants to convert that temperature from degrees Fahrenheit to degrees Celsius using the function [tex]$C(F)=\frac{5}{9}(F-32)$[/tex]. What does [tex]$C(F)$[/tex] represent? A. [tex]$C(F)$[/tex] represents the output of the function [tex]$C$[/tex] in degrees Celsius when the input [tex]$F$[/tex] is in degrees Fahrenheit B. [tex]$C(F)$[/tex] represents the output of the function [tex]$F$[/tex] in degrees Fahrenheit when the input [tex]$C$[/tex] is in degrees Celsius C. [tex]$C(F)$[/tex] represents the output of the function [tex]$C$[/tex] in degrees Fahrenheit when the input [tex]$F$[/tex] is in degrees Celsius D. [tex]$C(F)$[/tex] represents the output of the function [tex]$F$[/tex] in degrees Celsius when the input [tex]$C$[/tex] is in degrees Fahrenheit