According to the big bang theory, approximately when did the universe begin?

4 billion years ago

7 billion years ago

11 billion years ago

13 billion years ago

How many moles are contained in 3.131 * 1024 particles? A. 5.199 mol B. 18.85 mol C. 0.5199 * 1023 mol D. 1.885 * 1047 mol

A backpacker wants to carry enough fuel to heat 2.2 kg of water from 28 ∘C to 100.0 ∘C. If the fuel he carries produces 36 kJ of heat per gram when it burns, how much fuel should he carry?

How many grams would you have if you had 1.8 moles of aluminum bromide, AlBrz? Round your answer to two decimal places.

1) These are barrel shaped microtubules in most animal cells, that organize the spindles during cell division

Zinc metal can be obtained from zinc oxide ZNO by reacting the zinc oxide with the element carbon. The products of the reaction are ZN and CO2. what mass in grams of zinc oxide is needed to react completely with 5.00 mol of carbon?

2H2S (g) 2H2 (g) + S2 (g) Kc = 1.67 * 10 ^-7 at 800 C A 0.500 L reaction vessel initially contains 0.0125 mol of H2S at 800 C. Find the equilibrium concentrations of H2 and S2.

An atom has an atomic number of 9 a mass number of 19 and an electron configuration of 2-6-1 explain why the number of electrons in the second and third shells shows that this is in an excited state

How can a chemical reaction be sped up? Pack in more of the reactant to increase the_.

How does a mixture of benzoic acid and benzaldehyde can be isolated separately by extractions?

What is a compound? a) a combination of two or more substances that are not chemically combined b) a combination of two or more elements that are combined in a certain ratio