All categories

2 years ago

three of the following are base units used in the metric system. which is not a base unit? meter liter kilogram gram

1 answer:

8 0

The base units used in the metric system are meter for the measurement of distance or displacement, liter as unit measurement of volume, kilogram as a unit of measurement of mass and seconds as unit of measurement of time. The answer is here is D. gram.

You might be interested in

train travel from hong kong to beijing it traveled at an average speed of 160 km/m in the first 4 hours. after that it traveled

Nonamiya [84]

Answer:

7 hours

Explanation: step 1. 160x4=640

step 2. 1180-640=540

step 3. 540÷180=3

step 4. 3+4=7

5 0

3 years ago

Read 2 more answers

Calculate the enthalpy for this reaction: 2C(s) + H2(g) ---> C2H2(g) ΔH° = ??? kJ Given the following thermochemical equation

nordsb [41]

Answer:

The enthalpy for given reaction is 232 kilo Joules.

Explanation:

$C_2H_2(g) + \frac{5}{2}O_2(g)\rightarrow 2CO_2(g) + H_2O(l), \Delta H^o_{1} = -1,123 kJ$ ...[1]

$C(s) + O_2(g)\rightarrow CO2(g), \Delta H^o_{2} = -340 kJ$ ..[2]

$H_2(g) + \frac{1}{2}O_2(g)\rightarrow H_2O(l) ,\Delta H^o_{3} = -211 kJ$ ..[3]

$2C(s) + H_2(g)\rightarrow C_2H_2(g),\Delta H^o_{4} =?$ ..[4]

2 × [2] + [3] - [1] ( Using Hess's law)

$\Delta H^o_{4}=2\times \Delta H^o_{2}+\Delta H^o_{3} - \Delta H^o_{1}$

$\Delta H^o_{4}=2\times (-340 kJ) + (-211 kJ) - (-1,123 kJ)$

$\Delta H^o_{4}=232 kJ$

The enthalpy for given reaction is 232 kilo Joules.

5 0

2 years ago

Which of the following is a salt? C6H12O6 O2 C2H2 K C l

irina [24]

Answer:

it's kcl

Explanation:

the kcl should be salt

5 0

2 years ago

What are compounds?

hodyreva [135]

I think the correct answer is option A. Pure substances can be considered as compounds. Compounds are molecules made of atoms from different elements held together by chemical bonds. Pure substances are these compounds that exist alone no other substance.

8 0

3 years ago

The standard molar enthalpy of formation of NH3(g) is -45.9 kJ/mol. What is the enthalpy change if 9.51 g N 2(g) and 1.96 g H2(g

pogonyaev

Answer:

a. -29.8 kJ/mol-rxn

Explanation:

For a chemical reaction system the forward and reverse rate are equal. The standard molar enthalpy formation of NH3 is -45.9 kJ/mol. For the enthalpy of NH3 (8) the molar enthalpy is -29.8kJ/mol. The molar mass of N2 = 28.02g/mol. Molar enthalpy of formation is standard amount of substance produced in the formation of a reaction. The molar enthalpy is the change in enthalpy due to reaction per mole.

6 0

2 years ago