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The rate constant for the first-order decomposition of N2O is 3.40 s-1. What is the half-life of the decomposition? ** Don’t forget the units. round to the third decimal place [BLANK-1]

Which answer has 4 significant figures?

The sum of 26.83 + 2.7120 + 7.15 + 138.12 + 150.2619 expressed to the proper number of significant figures is:

Consider the following pairs of liquids. Which numbered response contains all the pairs that are miscible and non that are immiscible? I. Benzene (C6H6) and hexane (C6H14) II. Water (H2O) and methanol (CH3OH) III. Water (H2O) and hexane (C6H14)

Determine the rate law and the value of k for the following reaction using the data provided NO2(g) + O3(g) àNO3(g) + O2(g)                [NO2](M)                         [O3] (M)                           Initial Rate (M-1s-1)                   0.10                                    0.33                                    1.42                   0.10                                    0.66                                    2.84                   0.25                                    0.66                                    7.10

Consider the titrations of the pairs of aqueous acids and bases listed at the left. Which pair is incorrectly described (at the right) in terms of the acidic, basic or neutral character of the solutions ar the equivalence point?     Acid-Base Pair  Character at Equivalence Point  (A)    HClO + NaOH           acidic  (B)   HNO 3 + Ca(OH) 2           neutral  (C)  CH 3COOH  +  KOH           basic  (D)  HCl  +  NH 3           acidic  (E)  CH 3COOH  +  NH 3           neutral Hint: The conjugate base of a weak acid will hydrolyze water, similarly a conjugate acid of a weak base will hydrolyze water Example: HF + NaOH → H2O + F- + Na+; The F- is the conjugate base of the weak acid HF. The F- can react with water (hydrolysis) as shown below to produce OH- to make the equilibrium basic. F-  +  H2O  →  HF  +  OH-

Calculate the percent mass of nitrogen in ammonium carbonate (NH4)2CO3 Use: 7N14, 1H1, 6C12 and 8O16

Which noble gas configuration (short hand notation) is correct for 49In115 (Indium)?

Commercial grade HCl solutions are typically 39.0 % (w/w) HCl in water. Determine the molarity of the HCl, if the solution has a density of 1.2 g/mL. 

Determine the type of solid for each of the following compounds respectively MgO,  Cu,  CO2