All categories

2 years ago

How many joules of heat are lost by 1000g of granite as it cools from 41.2 Celsius to -12.9 Celsius?

Chemistry

1 answer:

lilavasa [31]2 years ago

8 0

Answer: The amount of heat released is 42739 Joules

Explanation:

The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

$Q=m\times c\times \Delta T$

Q = Heat released =?

c = heat capacity of granite = $0.790J/g^0C$

Initial temperature = $T_i$ = $41.2^0C$

Final temperature of the calorimeter = $T_f$ = $-12.9^0C$

Change in temperature , $\Delta T=T_f-T_i=(-12.9-41.2)^0C=-54.1^0C$

Putting in the values, we get:

$Q=1000g\times 0.790J/g^0C\times -54.1^0C=-42739J$

As heat comes out to be negative, that means the heat has been released and the amount of heat released is 42739 Joules

You might be interested in

for 2Na (s) +Cl2(g)->2NaCl(s) how many grams of sodium chloride will be made from 115 g of sodium metal when when reacted wit

alexandr1967 [171]

The grams of sodium chloride that will be made is 292.5 g

calculation

2Na +Cl₂ → 2NaCl

step 1: calculate the moles of Na

moles = mass/molar mass

From periodic table the molar mass of Na = 23 g/mol

moles = 115 g/23 g /mol = 5 moles

Step 2 : use the mole ratio to determine the moles of NaCl

Na:NaCl is 2:2 = 1:1 therefore the moles of NaCl is also= 5 moles

Step 3: find the mass of NaCl

mass= moles x molar mass

The molar mass of NaCl = 23 + 35 .5 =58.5 g/mol

mass= 5 moles x 58.5 g/mol =292.5 g

5 0

2 years ago

Please help

ryzh [129]

1. A double replacement chemical equation is a reaction in which the cations and anions of the compounds that react exchange their positions forming new compounds. Double replacement reaction usually leads to the formation of water, a precipitate or a gas as one of the products.

Example of a double replacement reaction:

$CaCl_{2}(aq)+Na_{2}SO_{4}(aq)-->CaSO_{4}(s)+2NaCl(aq)$

2. The above equation obeys the Law of conservation of mass as the number of atoms of each element on the reactant side is equal to that of the product side. So the overall mass on reactant side will be equal to that on the product side.

$CaCl_{2}(aq)+Na_{2}SO_{4}(aq)-->CaSO_{4}(s)+2NaCl(aq)$

Mass of each reactant per mole:

$(1 * Ca + 2 * Cl)=(1*40.08g/mol) + (2*35.45g/mol)=110.98g/mol$

$(2*Na)+(1*S)+(4*O)=(2*22.99g/mol)+(1*32.07g/mol)+(4*16.00g/mol)=142.04g/mol$

Total mass on reactant side = (110.98+142.04) g/mol= 253.02g/mol

Mass of each product per mole:

$(1*Ca)+(1*S)+(4*O)=(1*40.08g/mol)+(1*32.06g/mol)+(4*16.00g/mol)=136.14g/mol$

$(2*Na)+(2*Cl)=(2*22.99g/mol)+(2*35.45g/mol)=116.88g/mol$

Total mass on product side = (136.14+116.88)g/mol=253.02g/mol

Total mass on reactant side = Total mass on product side =253.02g/mol

So, it obeys the law of conservation of mass as the total mass remains same before and after the reaction.

3. In a chemical reaction, mass is conserved that means the mass of reacting species is equal to the mass of the products formed. Similarly the total number of atoms of each element is also conserved in a chemical reaction.

6 0

2 years ago

When one scientist repeats another scientist's experiment, he or she is probably trying to _____. A. show that he or she can do

aev [14]

Answer:

C. confirm the work of the other scientist

Explanation:

In formulating an acceptable hypothesis to back up a scientific finding, a scientist must make sure his experimental procedures are repeatable and falsifiable.

Repeatable experimental procedures allows for other scientists to critique a work. This can further throw more light into a finding and elevate the status of an observation to that of a theory or law. Other scientists repeats experiments in order to confirm the work of others if they are truly what they say they are.

5 0

2 years ago

Read 2 more answers

In an ionic bond, which category of elements are giving away electrons?

natima [27]

Ionic bonds form only between metals and nonmetals. That's because metals “want” to give up electrons, and nonmetals “want” to gain electrons. It takes energy to remove valence electrons from an atom and form a positive ion

6 0

2 years ago

Read 2 more answers

Add one or more curved arrows to show the movement of electrons in the reaction. To draw the arrows, select More in the drawing

DIA [1.3K]

Answer:

H3C - O - O - CH -HCOCH2.

Explanation:

Before chemical reaction can occur, some steps has to be followed in order to give the final product (s), this steps can be shown by drawing the chemical compound and showing how bonds are being broken or formed. Showing this in a stepwise manner is known as reaction mechanism.

From the question above, it is given that the products after heating the reactant gives H3C—0. +.0—CH HCO CH2.

The starting material can be deduce as;

H3C - O - O - CH -HCOCH2.

Heat causes something to divide or melt. Kindly check the attached picture which shows how the deduced starting compound splits to give H3C—0. and .0—CH HCO CH2.

3 0

2 years ago