Chemistry, 03.07.2021 15:30 ahmedeldyame

1) The percentage of oxygen in dry air is A. 0.1
B. 1.0
C. 21
D. 79

2) The composition of the Earth’s earliest atmosphere was different to that of the present atmosphere. Which of these gases was present in large amounts in the Earth’s earliest atmosphere?

A. Oxygen
B. Carbon dioxide
C. Ammonia
D. Nitrogen

Answers: 2

Show answers

Another question on Chemistry

Chemistry, 22.06.2019 06:30

If 1.8 l of water is added to 2.5l of a 7.0 molarity koh solution, what is the molarity of the new solution

Answers: 1

Answer

Chemistry, 22.06.2019 08:30

For each of the compounds below, show that the charges on the ions add up to zero. a. kbr b. cao c. li(2)o d. cacl(2) e. alcl(3)

Answers: 2

Answer

Chemistry, 22.06.2019 22:30

Which of the following is not an assumption that scientists must make about the natural world? a. regularity b. causality c. predictability d. plausibility

Answers: 1

Answer

Chemistry, 23.06.2019 02:00

The bone of a dinosaur and the imprint of a leaf are examples of which kind of fossils? a) index b) body c) amber d) trace

Answers: 1

Answer

You know the right answer?

1) The percentage of oxygen in dry air is A. 0.1
B. 1.0
C. 21
D. 79

...

Questions

Mathematics, 03.05.2020 14:12

A professor gives a multiple choice exam where each question has five choices. The professor decides not to count a question against students if the c...

English, 03.05.2020 14:12

How does a general Internet search up in the research process?...

History, 03.05.2020 14:12

“History of the Peloponnesian War: Pericles’ Funeral Oration:” How does the speaker gain the confidence of his listeners? a) ...

Mathematics, 03.05.2020 14:12

I need help ASAP ?!!. The questions are down below.

Mathematics, 03.05.2020 14:13

HELP PLEASE!! no comprende :(...

Mathematics, 03.05.2020 14:13

Sarah and Jenny are running a race. Sarah reaches the finish line, wow Jenny stopped 7/9 of the way. Draw a number line that shows where Jenny stopped...

History, 03.05.2020 14:13

What inference does kennedy make in this part of his speech?...

Mathematics, 03.05.2020 14:13

. The slope of the line is 4/9, and it contains the point (-6,8). Enter an equation in point-slope form...

Mathematics, 03.05.2020 14:13

CON V IEW Personal Math Trainer End-of-Year Test - Assessment « 1 2 3 4 5 6 7 8 9 10 >> Steven earns extra m...

Spanish, 03.05.2020 14:13

¿Por qué es importante tener un sistema de salud pública para las y los peruanos?...

Mathematics, 03.05.2020 14:13

Please Help me with my math...

Mathematics, 03.05.2020 14:13

What is the median of the following string of values? 75, 2, 44, 27, 8, 91, 18, 46, 38, 62...

Mathematics, 03.05.2020 14:13

Cause you know that charlie i i’m your biggest fan i’ll follow you until you notice me charlie charlie charlie...

History, 03.05.2020 14:13

Does anyone wanna get paid to do 10th grade work ?...

Mathematics, 03.05.2020 14:13

This is a type of proof where you show that a given statement can be deduced from basic truths....

Mathematics, 03.05.2020 14:13

Pls help me, i will really appreciate it. The question needs to be factorised

Biology, 03.05.2020 14:13

If linh removes bulb 3, which bulbs will remain lit...

Mathematics, 03.05.2020 14:13

The curved surface area of a solid cylinder is 660 cm2. what is a curved surface area...

Mathematics, 03.05.2020 14:13

The distance from the sun to the star Proxima Centauri is a little more than 4x10^16 meters. The distance from the sun to the cone nebula is about 8x1...

Mathematics, 03.05.2020 14:13

For the transformation T, write the T! T: (x, y) → (2x, y + 5) T''(x, y) → (x - 2.y-5) (Vax, y - 5) (2x - 1, y + 4)...

More questions: Chemistry Another questions