General Chemistry Answers

How can the presence of an ion in a solution be detected?

Suppose that when you run through a 50-meter distance you perform 2kJ of work. If before running, you eat food from which you obtain 800 J, would this activity cause you to slim down or to increase your weight? Explain.

20.0 g of KHCO3 are dissolved in 350 mL of solution

Gold melts at 1064 °C. Calculate the amount of thermal energy necessary to melt a gold ring weighing 8 g. Assume the ring starts at 25 °C. The specific heat capacity of gold is 0.129 J /g°C.

A. 1,098 J

B. 25.8 J

C. 1,072 J

D. 27,451 J

Part A

50 grams of ice-cold water (0 °C) is heated to boiling (100 °C). The specific heat capacity of water is 4.18 J /g°C. How much energy did the water absorb?

Part B

Over the next hour, the water gradually cools to 25 °C. How much energy did the water lose?

Hello people i need help for a question in my homework, the question is : Jack wants to blow 120 balloons of 20L each with helium, to do that he would need to buy helium gas tanks that contain 25L and the pressure of the tank is 6000kpa and has a temperature of 25 C, if the temperature in the room us 20C and the atmospheric pressure is 100Kpa when we are blowing the balloons , how many gas tanks should jack buy?

((This is the last thing I'll ask please just answer only these! ))

A) How many significant digits do the following measured quantities have?

i) 2.83 cm

iii) 14.0 g

v) 0.02 mL

vii) 2.350 x 10–2 L

ix) 3 fingers

ii) 36.77 mm

iv) 0.0033 kg

vi) 0.2410 km

viii) 1.00009 L

x) 0.0056040 g

B) How many significant digits do the following measured quantities have?

i) 83.25 – 0.1075

ii) 4.02 + 0.001

iii) 0.2983 + 1.52

C) How many significant digits do the following measured quantities have?

i) 7.255 ÷ 81.334

ii) 1.142 x 0.002

iii) 31.22 x 9.8

D) Solve the following:

i) 6.12 x 3.734 + 16.1 ÷ 2.3

ii) 0.0030 + 0.02

iii) 1.70 x 103 + 1.34 x 105

iv) (33.4 + 112.7 + 0.032)/(6.487)

E) Convert these measurements:

i) 1.0 cm = ______ m

ii) 0.0390 kg = ______ g

iii) 1.7 m = _____ mm

((Sorry for the trouble but I would just like this answered and not the previous comments))

-Cassi <3

Could you solve these?

i) 6.12 x 3.734 + 16.1 ÷ 2.3

ii) 0.0030 + 0.02

iii) 1.70 x 103+ 1.34 x 105

iv) (33.4 + 112.7 + 0.032)/(6.487)

• At which of the following temperature does water have the highest vapor pressure? 348K, 323K,  283K or 284K

How many Sig Digs are in each Q?

i) 2.83 cm

iii) 14.0 g

v) 0.02 mL

vii) 2.350 x 10–2 L

ix) 3 fingers

ii) 36.77 mm

iv) 0.0033 kg

vi) 0.2410 km

viii) 1.00009 L

x) 0.0056040 g

((I messed up the first 2 comments I sent so Im sending this one :) ))